Journal of Consciousness Studies, 25, No. 9–10, 2018, pp. 6–61
David J. Chalmers
The Meta-Problem
of Consciousness
The meta-problem of consciousness is (to a first approximation) the
problem of explaining why we think that there is a problem of
consciousness.1
Just as metacognition is cognition about cognition, and a metatheory is a theory about theories, the meta-problem is a problem about
a problem. The initial problem is the hard problem of consciousness:
why and how do physical processes in the brain give rise to conscious
experience? The meta-problem is the problem of explaining why we
think consciousness poses a hard problem, or in other terms, the problem of explaining why we think consciousness is hard to explain.
The relevant sort of consciousness here is phenomenal consciousness, or subjective experience.2 A system is phenomenally conscious
if there is something it is like to be that system, from the first-person
point of view. It is widely (although not universally) accepted that
most human beings are phenomenally conscious (at least when they
are awake), that bats, cats, and other non-human animals may well be
 1 For comments, thanks to <PRESIDIO_ANONYMIZED_PERSON>, Catarina Dutilh Novaes, Keith Frankish, Nick
Humphrey, François Kammerer, Jackson Kernion, Uriah Kriegel, Tom McClelland,
Luke McGowan, Kelvin McQueen, Luke Muehlhauser, Josh Weisberg, and David
Yates. Thanks also to audiences at ANU, Kansas, Marist College, Medellin, Melbourne,
Rutgers, Tiradentes, and the ASSC, Barcelona, and Tucson consciousness conferences.
2 I use ‘experience’, ‘conscious experience’, and ‘subjective experience’ more or less
interchangeably as synonyms for phenomenal consciousness (when used as mass nouns)
or for phenomenal states (when used as count nouns). Phenomenal states are ‘what-it-islike’ states: states individuated by what it is like to be in them (e.g. what it is like to see
a certain shade of red or to feel a specific sort of pain). Phenomenal properties are
‘what-it-is-like’ properties: properties individuated by what it is like to have them.
Correspondence:
Email: <PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
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THE META-PROBLEM OF CONSCIOUSNESS 7
phenomenally conscious, and that trees and rocks are not. A mental
state is phenomenally conscious when there is something it is like to
be in that state. It is widely accepted that seeing a bright red square
and feeling pain are phenomenally conscious, and that one’s ordinary
background beliefs (my belief that Paris is in France, say, when I am
not thinking about the matter) are not.
The hard problem of explaining phenomenal consciousness is one of
the most puzzling in all of science and philosophy, and at the present
time there are no solutions that command any sort of consensus. The
hard problem contrasts with the easy problems of explaining various
objective behavioural or cognitive functions such as learning,
memory, perceptual integration, and verbal report. The easy problems
are easy because we have a standard paradigm for explaining them. To
explain a function, we just need to find an appropriate neural or computational mechanism that performs that function. We know how to
do this at least in principle. In practice, the cognitive sciences have
been making steady progress on the easy problems.
On this analysis, the hard problem is hard because explaining consciousness requires more than explaining objective behavioural or
cognitive functions. Even after we have explained all the objective
functions that we like, there may still remain a further question: why
is all this functioning accompanied by conscious experience? When a
system is set up to perform those functions, from the objective point
of view, why is there something it is like to be the system, from the
subjective point of view? Because of this further question, the standard methods in the cognitive sciences have difficulty in gaining
purchase on the hard problem.
There is nevertheless one behavioural function that has an especially
close tie to the hard problem. This behavioural function involves
phenomenal reports: the things we say about consciousness (that is,
about phenomenal consciousness). More specifically, many people
make problem reports expressing our sense that consciousness poses a
hard problem. I say things like ‘There is a hard problem of consciousness’, ‘It is hard to see how consciousness could be physical’,
‘Explaining behaviour does not explain consciousness’, and so on. So
do many others. It is easy to get ordinary people to express puzzlement about how consciousness could be explained in terms of brain
processes, and there is a significant body of psychological data on the
‘intuitive dualist’ judgments of both children and adults.
The meta-problem of consciousness is (to a second approximation)
the problem of explaining these problem reports. Problem reports are
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8 D.J. CHALMERS
a fact of human behaviour. Because of this, the meta-problem of
explaining them is strictly speaking one of the easy problems of consciousness. At least if we accept that all human behaviour can be
explained in physical and functional terms, then we should accept that
problem reports can be explained in physical and functional terms. For
example, they might be explained in terms of neural or computational
mechanisms that generate the reports.
Although the meta-problem is strictly speaking an easy problem, it
is deeply connected to the hard problem. We can reasonably hope that
a solution to the meta-problem will shed significant light on the hard
problem. A particularly strong line holds that a solution to the metaproblem will solve or dissolve the hard problem. A weaker line holds
that it will not remove the hard problem, but it will constrain the form
of a solution.
Like the hard problem, the meta-problem has a long history. One
distinguished tradition involves materialists, who hold that the mind is
wholly physical, trying to undermine dualist opponents by explaining
away our intuitive judgment that the mind is non-physical. One can
find versions of this strategy in historical philosophers such as
Hobbes, Hume, Spinoza, and Kant. For example, in the first paralogism in the Critique of Pure Reason (1781/1999), Kant argues that a
‘transcendental illusion’ is responsible for our intuition that the self is
a simple substance. More recently, U.T. Place (1956) diagnoses
dualist intuitions about consciousness as resting on a ‘phenomenological fallacy’, David Armstrong (1968a) diagnoses them as resting
on a ‘headless woman illusion’, and Daniel Dennett (1992) diagnoses
them as resting on a ‘user illusion’.
This strategy typically involves what Keith Frankish (2016) has
called illusionism about consciousness: the view that consciousness is
or involves a sort of introspective illusion. Frankish calls the problem
of explaining the illusion of consciousness the illusion problem. The
illusion problem is a close relative of the meta-problem: it is the
version of the meta-problem that arises if one adds the thesis that
consciousness is an illusion. Illusionists typically hold that a solution
to the meta-problem will itself solve or dissolve the hard problem. For
example, if we have a physical explanation of why it seems to us that
we have special non-physical properties, then those properties can be
dismissed as an illusion, and any problem in explaining them can be
dismissed as resting on an illusion. Views like this have been held or
explored in recent years by philosophers such as Daniel Dennett,
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THE META-PROBLEM OF CONSCIOUSNESS 9
Frankish, and Derk Pereboom, and scientists such as Michael
Graziano and Nicholas Humphrey.3
As a result, the meta-problem is especially important for illusionists.
The best arguments for illusionism (as I will discuss toward the end of
this article) are so-called debunking arguments that rest on there being
a solution to the meta-problem that explains our beliefs about consciousness without invoking consciousness. If a consensus solution of
this sort ever develops, then support for illusionism may swell. Even
without a consensus solution to the meta-problem, thinking hard about
the meta-problem may well make illusionism more appealing to more
people. Speaking for myself: I have said before (e.g. Chalmers, 1996,
p. 189) that if I were a materialist, I would be an illusionist. I think
that, if anything, illusionism has been under-explored in recent years. I
take the view seriously, and I have more sympathy with it than with
most materialist views.4
That said, I am not an illusionist. On my view, consciousness is real,
and explaining our judgments about consciousness does not suffice to
solve or dissolve the problem of consciousness. But the meta-problem
is not just a problem for illusionists. It is a problem for everybody.
I have long thought that solving the meta-problem might be a key to
solving the problem of consciousness.5 Even a non-illusionist can
 3 See Dennett (2016), Frankish (2016), Graziano (2013), Humphrey (2011), and
Pereboom (2011) (although only the first two explicitly endorse illusionism). Some
other recent illusionists may include: (philosophers) Clark (2000), Kammerer (2016),
Rey (1996), Schwarz (forthcoming); (others) Argonov (2014), Blackmore (2002),
Drescher (2006), Muehlhauser (2017).
4 Upon hearing about this article, some people have wondered whether I am converting to
illusionism, while others have suspected that I am trying to subvert the illusionist programme for opposing purposes. Neither reaction is quite correct. I am really interested
in the meta-problem as a problem in its own right. But if one wants to place the article
within the framework of old battles, one might think of it as lending opponents a
friendly helping hand.
5 My first serious article on consciousness (Chalmers, 1987) argued that almost any
intelligent machine would say that it is conscious and would be puzzled about consciousness, and argued from here that any convincing theory of consciousness must
grant consciousness to machines. A subsequent article, ‘Consciousness and Cognition’
(Chalmers, 1990), proposed a test for theories of consciousness along lines of the metaproblem challenge discussed later in this article, holding that these theories should be
able to explain reports about consciousness in a way that coheres with their explanation
of consciousness itself. That article also proposed a solution to the meta-problem, which
I developed further in The Conscious Mind (1996, pp. 184–8 and pp. 289–92) and
which I used to motivate the information-based theory of consciousness that I favoured
at that time.
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10 D.J. CHALMERS
reasonably hope both that there be an explanation of our judgments
about consciousness and that this solution will give us insight into
consciousness itself. Presumably there is at least a very close tie
between consciousness and the mechanisms that generate reports
about it. Perhaps consciousness itself plays a key role in the
mechanisms, or perhaps those mechanisms serve somehow as the
basis of consciousness. Either way, understanding the mechanisms
may well take us some distance in understanding consciousness.
In effect, the meta-problem subsumes the illusion problem while
being more general and more neutral. The meta-problem is neutral on
the existence and nature of consciousness, while the illusion problem
presupposes an extremely strong view about the existence and nature
of consciousness. Since illusionism is held only by a small minority of
theorists, it makes sense for the community as a whole to understand
the problem as the meta-problem and focus on solving it.6 Theorists
can then draw their own conclusions about what follows.
The meta-problem opens up a large and exciting empirical and
philosophical research programme. The question of what mechanisms
bring about our problem reports is in principle an empirical one. We
can bring philosophical methods to bear on assessing solutions but, as
with the other ‘easy problems’, the methods of psychology, neuroscience, and other cognitive sciences will play a crucial role.
In practice, one can already see the glimmer of a research programme that combines at least (i) work in experimental philosophy,
experimental psychology, linguistics, and anthropology studying subjects’ judgments about consciousness, (ii) work in psychology and
neuroscience on the mechanisms that underlie our self-models and
bring about problem reports and other phenomenal reports, (iii) work
in artificial intelligence and computational cognitive science on computational models of phenomenal reports, yielding computational
systems that produce reports like ours, and (iv) philosophical
 6 I suggested the name ‘illusion problem’ to Frankish, who had previously been calling
the illusionist version of the problem the ‘magic problem’ (a name with its own limitations). Mea culpa. I should also note that related ‘meta’ problems have been suggested
by Andy Clark (2001) and François Kammerer (2018a). Clark’s ‘meta-hard problem’ is
the problem of whether there is a hard problem of consciousness. Kammerer’s ‘illusion
meta-problem’ is the problem of why illusionism about consciousness is so hard to
accept. These problems are distinct from what I am calling the meta-problem, but they
are certainly related to it.
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THE META-PROBLEM OF CONSCIOUSNESS 11
assessment of potential mechanisms, including how well they match
up with and explain philosophical judgments about consciousness.
The meta-problem is a problem for scientists and philosophers alike,
reductionists and non-reductionists alike, dualists and physicalists
alike, illusionists and non-illusionists alike. For the most part, this
paper will take an ecumenical approach that I hope will be interesting
to people on all sides of these divides. I am most interested to explore
the meta-problem as a problem in its own right. In the first half of the
paper, after clarifying what the meta-problem involves, I will present
and evaluate a number of potential solutions to the meta-problem. In
the second half of the paper, I will explore how the meta-problem may
impact scientific and philosophical theories of consciousness,
including both realist and illusionist theories.
1. The Meta-Problem Research Programme
I introduced the meta-problem as the problem of explaining why we
think there is a problem of consciousness. I elaborated it as the problem of explaining our problem reports, where these are our reports
about consciousness that reflect our sense that consciousness poses a
special problem. It is time to be a bit more specific about what this
comes to: in particular, what needs to be explained, and what sort of
explanation counts.
1.1. What needs to be explained?
What exactly are the problem data that need explaining? They can be
construed as verbal reports (my saying ‘Consciousness is hard to
explain’), as judgments (my forming the judgment that consciousness
is hard to explain), or as dispositions to make these reports and judgments. Verbal reports are perhaps the most objective data here, but
they are also a relatively superficial expression of an underlying state
that is really what we want to explain. So I will generally focus on
dispositions to make verbal reports and judgments as what we want to
explain.
I will call dispositions to make specific problem reports and judgments problem intuitions. I will also use the term to apply to the problem reports and judgments themselves. There may be more to the
states ordinarily called intuitions than this, but it is plausible that they
at least involve these dispositions and judgments. As I am using the
term, problem intuitions can result from inferences, so that judgments
that result from philosophical arguments will count as problem
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12 D.J. CHALMERS
intuitions. Still, it is plausible that, in solving the meta-problem, the
most important problem intuitions will be non-inferential judgments
that arise prior to philosophical argument, and I will focus especially
on judgments of this sort.
Next, which intuitions need to be explained to solve the metaproblem? In principle phenomenal reports include any reports about
consciousness, including mundane reports such as ‘I am feeling pain
now’. The problem of explaining the corresponding intuitions is
certainly an interesting problem. The meta-problem proper, however,
is the problem of explaining problem intuitions: intuitions that reflect
our sense that there is some sort of special problem involving consciousness, and especially some sort of gap between physical processes and consciousness. For example, ‘I can’t see how consciousness could be physical’ is a problem report, and the disposition to
judge and report this is a problem intuition.
Problem intuitions divide into a number of categories. Perhaps the
core intuitions for the meta-problem as defined are explanatory
intuitions holding that consciousness is hard to explain. These include
gap intuitions holding that there is an explanatory gap between
physical processes and consciousness, and anti-functionalist intuitions
holding that explaining behavioural functions does not suffice to
explain consciousness. Closely related are metaphysical intuitions,
including dualist intuitions holding that consciousness is non-physical,
and fundamentality intuitions holding that consciousness is somehow
fundamental or simple. There are also knowledge intuitions: these
include both first-person knowledge intuitions holding that consciousness provides special knowledge from the first-person perspective
(like Mary’s knowledge of what it is like to see red on leaving the
black and white room), and third-person ignorance intuitions, such as
the intuition that it is hard to know the consciousness of other people
or other organisms (such as what it is like to be a bat). There are
modal intuitions about what is possible or conceivable, including the
‘zombie’ intuition that a physical or functional duplicate of us might
lack consciousness, and ‘inversion’ intuitions, such as that someone
else might be experiencing red when I experience green.
I will take these four classes (explanatory, metaphysical, knowledge, and modal intuitions) to be the central cases of problem
intuitions, with the first two being the most central. There are also
some nearby intuitions that are closely related. For example, there are
value intuitions, holding that consciousness has special value: perhaps
that it makes life worth living, for example. There are distribution
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THE META-PROBLEM OF CONSCIOUSNESS 13
intuitions, concerning which systems do and don’t have consciousness: for example, the common intuition that robots are not conscious
is a distribution intuition. There are self intuitions concerning the self
or the subject of experience. There are quality intuitions concerning
the special qualities (colours and the like) that are presented in experience, and presentation intuitions concerning the direct way they are
presented to us. The list goes on. I will not attempt to draw up a full
list here.
The range of these intuitions is an empirical question. I could
perhaps be accused of focusing on the intuitions of philosophers, and
of a subclass of philosophers at that. But I think the central intuitions
are widely shared well beyond philosophy. It is highly plausible that
versions of many of these intuitions can be teased out of ordinary subjects, but it is an empirical matter just how widespread they are.
There is a large body of research in experimental psychology and
experimental philosophy on people’s intuitions about the mind, but
surprisingly little of it to date has concerned core intuitions about the
problem of consciousness. Perhaps the largest body of research concerns children’s intuitions about belief: for example, does a threeyear-old have the concept of false belief? Another large body concerns
intuitions about the self and personal identity: for example, do people
think that the self goes with the body or the brain in a brain transplant
case? Where consciousness is concerned, the largest body of research
concerns the distribution of consciousness (e.g. Gray, Gray and
Wegner, 2007; Knobe and Prinz, 2008; Sytsma and Machery, 2010):
for example, do people think that machines or corporations can feel
pain? Some attempts have been made to connect this research to the
hard problem of consciousness,7 but for the most part the intuitions in
question have not been the core problem intuitions.
 7 For example, Sytsma and Machery (2010) observe that ordinary subjects are much more
likely to say that a robot can see red than that it can feel pain, and they conclude that
ordinary subjects do not have a unified category of phenomenal consciousness, subsuming seeing red and feeling pain, that generates the hard problem. In fact this result is
predicted by Chalmers (1996, p. 18), which observes that ordinary mental terms like
this have both a functional reading and a phenomenal reading, with sensational terms
such as ‘pain’ more likely to suggest a phenomenal reading than perceptual terms such
as ‘see’. I think many or most subjects have concepts of specific phenomenal states such
as feeling pain or experiencing colour, but I am neutral on whether they also have a
unifying concept of phenomenal consciousness. Certainly the most common problem
intuitions (e.g. colour inversion intuitions) seem to involve these specific phenomenal
concepts. Other relevant experimental work includes Huebner (2010), Talbot (2012),
and Peressini (2014). Relatedly, Wierzbicka (2010) uses cross-linguistic analysis to
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What about experimental research on the core problem intuitions?
In principle there is room for experimental work on conceivability
intuitions (e.g. the conceivability of zombies) or knowledge intuitions
(e.g. Mary’s knowledge in and out of her black and white room), but I
do not know of any work along these lines to date. Where metaphysical intuitions are concerned, there is a non-negligible body of
literature on ‘intuitive dualism’ (e.g. Bloom, 2004; Chudek et al.,
2013; Richert and Harris, 2008), but the main body of this research
largely focuses on intuitions about the self (e.g. could a self move
between bodies or survive bodily death?) rather than about consciousness per se. There is a small body of relevant work on explanatory
intuitions. For example, Gottlieb and Lombrozo (2018) elicit judgments about when various phenomena are hard for science to explain,
and find that people judge that phenomena tied to subjective experience and to privileged access are relatively hard to explain.8
As a result, it is hard to know how widely shared the problem
intuitions are. It is clear that they are not universal, at least at the level
of reflective judgment. All of them are rejected by some people. In
many cases of rejection, there is an underlying intuition that is
psychologically outweighed by other forces (for example, an inclination towards dualism might be outweighed by reasons to accept
physicalism), but it is not obvious that there is always such an underlying intuition. A fully adequate solution to the meta-problem should
be able to explain not only why these intuitions are widely shared, if
they are, but also why they are not universal, if indeed they are not.9
 argue that an Anglophone background has distorted analytic philosophers’ discussion of
experience and related concepts.
8 One related empirical study is the PhilPapers Survey of professional philosophers
(Bourget and Chalmers, 2014) — although this study is not really experimental, and
most questions concern considered judgments rather than immediate intuitions. The
survey found that 36% of the target group judge that zombies are conceivable but not
metaphysically possible, 16% judge that they are inconceivable, and 23% judge that
they are metaphysically impossible (with 25% agnostic or giving other answers). 56%
endorsed physicalism about the mind while 27% endorsed non-physicalism about the
mind.
9 For what it’s worth, I predict that knowledge intuitions will be somewhat more widespread than conceivability intuitions, and that explanatory intuitions will be somewhat
more widespread than metaphysical intuitions. Intuitions about Mary-style cases and
inversion case (‘your green could be my red’) may be particularly robust. But, as
always, a great deal will depend on the way that key claims are formulated (this may be
particularly difficult where conceivability arguments are concerned). Furthermore, the
fact that someone denies a key claim (say, that consciousness is non-physical) is consistent with their having an underlying intuition that is outweighed.
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THE META-PROBLEM OF CONSCIOUSNESS 15
As a first approximation, I will work under the assumption that
these intuitions are widely shared, or at least that they have a widely
shared basis. This is an empirically defeasible assumption, and I
would be delighted to see empirical research (including cross-cultural,
developmental, and historical research) that tests it.10 Human
intuitions and reports about the mind are plausibly produced by a
combination of near-universal factors (e.g. mental states and introspective mechanisms that most humans share) and more variable
factors (e.g. cultural, linguistic, and theoretical background, and other
factors that vary with historical period and individual psychology).
Variable factors will yield a great deal of variation in reports and
intuitions, and may sometimes overwhelm the contribution of more
universal factors. Still, my working assumption is that there are also
near-universal factors that play a central underlying role in explaining
problem intuitions where they are present.
Even if the assumption is false, the more limited task of explaining
the intuitions in people who have them (presumably in terms of
variable factors) will still be of considerable interest. For example, it
will still be crucial for illusionists to explain those intuitions, in order
to make the case that they are illusory. Solving the meta-problem will
remain an important project either way.
1.2. What counts as an explanation?11
What sort of explanation counts as an explanation of problem
intuitions, for the purposes of the meta-problem? For example, does it
count as an explanation to say that we judge that consciousness poses
a problem because consciousness does indeed have certain problematic features, and we notice that? In some contexts that may count
as a reasonable explanation. Still, this sort of explanation is no longer
neutral between realism and illusionism, and it threatens to turn the
easy problem of explaining phenomenal intuitions back into a hard
problem, because we will need to explain consciousness to explain the
intuitions.
 10 In the related domain of intuitions about the transfer of selves between bodies, Chudek
et al. (2013) give cross-cultural evidence against the hypothesis of ‘culturally acquired
dualism’ and in favour of a more universal ‘intuitive dualism’.
11 This section goes into a bit more philosophical detail than other sections and can easily
be skipped by readers without much background in philosophy.
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For our purposes, it is useful to put more constraints on a solution to
the meta-problem. Earlier I suggested that a solution would involve a
physical or functional explanation (roughly, one in terms of neural or
computational mechanisms), but it is useful to impose a more general
constraint.
I understand the meta-problem as the problem of explaining
phenomenal reports in topic-neutral terms: roughly, terms that do not
mention consciousness (or cognate notions such as qualia, awareness,
subjectivity, and so on). Physical and functional explanations will be
topic-neutral explanations, but so will some other explanations,
including representational, rational, historical, and structural
explanations.
Representational explanation allows us to explain problem intuitions
in terms of internal states or models that represent the subject or the
world as having certain properties. Rational explanations explain processes as doing certain things because they are rational. It may be
desirable that such an explanation can eventually be cashed out as a
physical/functional explanation, but as long as it does not directly
mention consciousness or cognates, it will count as a topic-neutral
explanation.
Historical explanations are especially important. We do not just
want to know (synchronically) how problem intuitions are produced.
We want to know how problem-intuition-producing systems came to
exist in the first place. Why were phenomenal intuitions a good idea?
What evolutionary function did they serve, if any? A solution that
gives a well-motivated story about the evolution of phenomenal
intuitions will be more satisfactory than one that does not. In any case,
a complete solution to the meta-problem should say something about
these historical and teleological questions.
Structural explanations allow the meta-problem to generalize to
views where not all behaviour can be explained in physical terms. For
example, consider an interactionist dualist view on which consciousness is non-physical and interacts with the brain. Descartes held that
the non-physical mind drives brain processes via the pineal gland,
while some contemporary interactionists hold that non-physical consciousness drives physical processes by collapsing a quantum wave
function. On these views, one can still ask what explains problem
reports and the like. Presumably the interactionist will hold that
physical processes do not explain these reports, and that non-physical
consciousness plays a central role in the explanation. But many
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THE META-PROBLEM OF CONSCIOUSNESS 17
interactionists will also be able to give structural explanations that do
not mention consciousness.
For example, suppose that non-physical consciousness is arranged
in such a way that it carries out a specific computation (in ectoplasm,
say), and its causal role always goes through the outcome of such a
computation. Then we could explain human behaviour in computational terms without ever mentioning consciousness. Or suppose that
non-physical consciousness always collapses the quantum wave
function in certain specifiable circumstances according to the standard
probabilities (given by the Born rule). Then in principle we could
explain human behaviour in structural terms by saying that there is
something that collapses the wave function in those circumstances,
without ever saying that what does the collapsing is consciousness. In
principle this would yield a topic-neutral explanation of problem
reports.
This brings out an important point: a topic-neutral solution to the
meta-problem does not require that consciousness is causally or
explanatorily irrelevant. On the interactionist views just discussed,
consciousness will play a causal role in generating behaviour
(including problem reports), and a truly complete explanation of
human behaviour will mention consciousness. Nevertheless, it will be
possible to give a good (if not truly complete) explanation of human
behaviour in topic-neutral terms that do not mention consciousness.
This is roughly analogous to the way that, on a standard physicalist
view, neurons play a crucial causal role in generating behaviour, but it
is nevertheless possible to give a computational explanation of human
behaviour that does not mention neurons. In effect, the topic-neutral
explanation specifies a structure, and neurons (or consciousness) play
their role by undergirding or realizing that structure.
Structural explanations also apply to various forms of panpsychism
and Russellian monism. On these views, consciousness or protoconsciousness at the fundamental level serves as the basis of the
microphysical roles specified in physics. On these views, consciousness plays a causal role in generating human behaviour. It will nevertheless be possible to explain physical processes in topic-neutral
mathematical terms that do not mention consciousness. Again, there
may be something incomplete about this topic-neutral explanation, but
it will still be an explanation. In principle, panpsychism is no obstacle
to there being a solution to the meta-problem in topic-neutral terms.
Some theorists may nevertheless hold that there is no good explanation of problem intuitions in topic-neutral terms. For example, there
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18 D.J. CHALMERS
may be anomalous dualist views on which consciousness plays a completely unpredictable role, with effects that somehow depend on the
intrinsic non-structural features of consciousness itself. One could try
to turn this structure into a topic-neutral explanation, but it is not clear
that an adequate topic-neutral explanation will always be available.
Likewise, some anomalous monists and others might also argue
against there being good physical explanations of behaviour, even
though physicalism is true. To accommodate views like this, we can
understand the meta-problem somewhat more generally as the problem of explaining problem intuitions in topic-neutral terms, or
explaining why no such explanation is possible.
A subtlety of the move to topic-neutral terms is that we have to
reconstrue what we are explaining — problem intuitions — in topicneutral terms. As initially described, problem intuitions concern consciousness, so that explaining them requires saying something specific
about consciousness. Some problem intuitions may even concern
specific phenomenal qualities such as the quality of pain. It is far from
clear that the fact that our intuitions concern phenomenal properties
can itself be explained in topic-neutral terms. Many theorists
(including me) hold that these phenomenal beliefs turn on the
existence of consciousness itself, so they cannot be fully explained in
topic-neutral terms. To handle this, we need to reconstrue problem
intuitions themselves in topic-neutral terms.
There are a couple of ways to do this. One could put phenomenal
intuitions in an existential form, such as ‘We have special properties
that are hard to explain’ or ‘that are non-physical’, ‘that provide
special first-person knowledge’, ‘that could be missing in robots’, and
so on. Alternatively, one could simply require that phenomenal
intuitions be explained up to but not including the fact that they are
specifically about consciousness. Once we have explained judgments
of the form ‘We have special first-person knowledge of X which is
hard to explain in physical terms’, and so on, we have done enough to
solve the meta-problem. In the language of Chalmers (2007), we can
call these quasi-phenomenal judgments. Quasi-phenomenal judgments
do not so obviously depend on consciousness, and might even be
shared by zombies.
A related issue is that some people think that all judgment involves
an element of consciousness, or that all meaningful language is
grounded in consciousness, so that it is impossible to explain
genuinely meaningful reports or judgments in topic-neutral terms. If
one holds this view, one should understand problem intuitions as
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THE META-PROBLEM OF CONSCIOUSNESS 19
involving something less than full-scale reports and judgments.
Perhaps they are mere propensities to make certain noises and
inscriptions (naturally interpretable as concerning consciousness).
That will at least leave open the possibility that problem intuitions can
be explained in topic-neutral terms.
For some purposes realists may want to relax the topic-neutrality
constraint. To fully develop a realist view of consciousness, it may
well be crucial to focus on full-scale phenomenal beliefs and to
explain these things in terms of consciousness. Still, for my current
purposes of understanding the meta-problem as an easy problem, I
will mainly adopt the topic-neutral approach in what follows.
2. Potential Solutions to the Meta-Problem
It is time to face up to the meta-problem: explain our problem
intuitions in topic-neutral terms, or explain why this is impossible.
In what follows I will examine a number of candidate solutions to
the meta-problem, involving topic-neutral explanations of our problem
intuitions, focusing on their strengths and limitations. Many of these
ideas have been put forward in the literature, often more than once. It
is typical of proposals about the meta-problem that they are made in
isolation from other proposals, often without acknowledging any other
work on the subject. I hope that bringing these proposals together will
contribute to a more integrated research programme in the area.12
The proposals I consider are not mutually exclusive, and many of
them work well together. The first seven or so proposals are ideas that
I find especially promising. I think all of these ideas may form part of
a correct account. After these, I will also discuss some ideas from
others that I am less inclined to endorse, but which are nevertheless
useful or instructive in thinking about the meta-problem. My overall
aim is constructive: I would like to build a framework that may lead to
a solution to the meta-problem. At the same time, I will be pointing
out limitations and challenge that each of these ideas face, in order to
 12 Two other authors who in effect consider and criticize multiple solutions to the metaproblem include Bogardus (2013), who argues that proposals (discussed in what
follows) due to Fiala, Nagel, Loar, and Papineau, and others concerning the source of
our dualist intuitions do not succeed as defeaters for arguments for dualism, and
Kammerer (2018a), who argues that proposals due to Graziano and Pereboom cannot
solve his ‘illusion meta-problem’ discussed earlier.
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clarify some of the further work that needs to be done for a convincing
solution to the meta-problem.
I will often approach the meta-problem from the design stance. It
may help to think of building a robot which perceives the world, acts
on the world, and communicates. It may be that certain mechanisms
that are helpful for the robot, for example in monitoring its own states,
might also generate something like problem intuitions. At the same
time I will keep one eye on what is distinctive about phenomenal
intuitions in the human case. Contrasting these intuitions with our
related intuitions about phenomena such as colour and belief can help
us to determine whether a proposed mechanism explains what is
distinctive about the phenomenal case.
1. Introspective models. An obvious place to start is that any intelligent system will need representations of its own internal states. If a
system visually represents a certain image, it will be helpful for it to
represent the fact that it represents that image. If a system judges that
it is in danger, it will be helpful for it to represent the fact that it
judges this. If a system has a certain goal, it will be helpful for it to
represent the fact that it judges this. In general, we should expect any
intelligent system to have an internal model of its own cognitive
states. It is natural to hold that our phenomenal intuitions in general
and our problem intuitions more specifically arise from such an
internal model.13
While this claim may be a key element of any solution to the metaproblem, it does not itself constitute anything close to a solution. For it
to yield a solution, one would need an explanation of why and how
our internal self-models produce problem intuitions. I have occasionally heard it suggested that internal self-models will inevitably produce problem intuitions, but this seems clearly false. We represent our
own beliefs (such as my belief that Canberra is in Australia), but these
representations do not typically go along with problem intuitions or
anything like them. While there are interesting philosophical issues
about explaining beliefs, they do not seem to raise the same acute
 13 Many attempts at solving the meta-problem give a role to introspective models. Introspective models are especially central in Graziano’s (2013) ‘attention schema’ theory of
consciousness, which explains our sense of consciousness as a model of attention.
Metzinger (2003) focuses on ‘phenomenal self-models’ that appeal to phenomenal
properties to explain certain illusory beliefs about the self, rather than beliefs about
phenomenal properties. Hofstadter (2007) also develops a sort of illusionism based in
self-models and self-reference, primarily directed at illusions about the self.
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THE META-PROBLEM OF CONSCIOUSNESS 21
problem intuitions as do experiences. Some people claim to have a
non-sensory experience of thinking, but these intuitions are much less
universal and also less striking than those in the case of sensory
experience. Even if there are such experiences, it is not clear that
introspecting one’s beliefs (e.g. that Paris is the capital of France)
always involves them. So more is needed to explain why the
distinctive intuitions are generated in the phenomenal case.
2. Phenomenal concepts. Another obvious starting point focuses on
our concepts of consciousness, or phenomenal concepts. These function as special concepts to represent our phenomenal states, especially
when we detect those states by introspection. The well-known
phenomenal concept strategy tries to explain many of our problem
intuitions in terms of features of our phenomenal concepts. If this
works, and if the relevant features can then be explained in topicneutral terms, we will then have a solution to the meta-problem.14
I have criticized the phenomenal concept strategy elsewhere
(Chalmers, 2007), arguing that there are no features of phenomenal
concepts that can both be explained in physical terms and that can
explain our epistemic situation when it comes to consciousness. In
that paper I construed the phenomenal concept strategy as a version of
‘type-B’ materialism, which accepts a robust understanding of our
epistemic situation on which many of our problem intuitions (e.g.
knowledge and conceivability intuitions) are correct. To solve the
meta-problem, however, we need only explain the fact that we have
the problem intuitions; we do not also need to explain their correctness. There is an illusionist (or ‘type-A’) version of the phenomenal
concept strategy which holds that our problem intuitions are incorrect
and our epistemic situation is not as we think it is (e.g. Mary does not
gain new knowledge on seeing red for the first time), but on which
features of phenomenal concepts explain why we have the intuitions
in the first place. This use of phenomenal concepts is explicitly set
aside in my earlier paper and is not threatened by the critique there.
Still, everything depends on what the account says about phenomenal concepts. In the earlier paper, I argued on the most common
accounts where the features of phenomenal concepts can be physically
 14 The locus classicus of the phenomenal concept approach is Loar’s (1990) appeal to
recognitional concepts. Also relevant is the appeal to indexical concepts by Ismael
(1999) and Perry (2001), the appeal to quotational concepts by Balog (2009) and
Papineau (2007), and others.
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explained, the concepts are too ‘thin’ to explain our problem
intuitions. For example, the suggestion that phenomenal concepts are
indexical concepts such as ‘this state’ does not really explain our
knowledge intuitions and others: when we pick out a state indexically
as ‘this state’, we are silent on its nature and there is no obvious
reason why it should generate problem intuitions. Similarly, the
suggestions that phenomenal concepts are recognitional concepts akin
to our concepts of a certain sort of cactus also do not explain the
problem intuitions. When we recognize a cactus, we do not have problem intuitions anything like those we have in the phenomenal case.
Something similar goes for many extant suggestions. It may be that
some other feature of phenomenal concepts can both explain our
problem intuitions and be explained in physical terms, but if so it is
this feature that will be doing the explanatory work.
3. Independent roles. It is sometimes suggested that many of our
problem intuitions can be explained by the fact that physical and
phenomenal concepts have independent conceptual roles, without
strong inferential connections from one to the other. For example,
Nagel (1974) suggests that our conceivability intuitions might be
explained by the fact that physical concepts are tied to perceptual
imagination and phenomenal concepts are tied to sympathetic
imagination, and these two forms of imagination are independent of
each other. This approach has been taken more generally by Hill and
McLaughlin (1999) and others who hold that the fact that phenomenal
concepts and physical concepts have independent roles can explain
our explanatory intuitions and knowledge intuitions as well as conceivability intuitions.
There is certainly something to this view, but it suffers from a
familiar problem: our concepts of belief also seem independent from
our physical concepts, but they do not generate the same problem
intuitions. Phenomenal states seem problematic in large part because
they seem to have a specific qualitative nature that is hard to explain
in physical terms (where beliefs do not), and this seeming is not
explained simply by the independence of phenomenal concepts. Ultimately, we need to explain why these qualitative properties seem to
populate our minds, which requires an account of why we have introspective concepts that attribute these qualitative properties. Merely
pointing to the independence of introspective concepts does not
explain this.
4. Introspective opacity. A central element of many attempts to
address the meta-problem turns on the fact that the physical
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mechanisms underlying our mental states are opaque to introspection.
We do not represent our states as physical, so we represent them as
non-physical. In the locus classicus of this approach, David
Armstrong (1968a) makes an analogy with the ‘headless woman’
illusion. A sheet covers a woman’s head, so we do not see her head.
As a result, she seems to be headless. Armstrong suggests that we
somehow move from ‘I do not perceive that the woman has a head’ to
‘I perceive that the woman has no head’. Likewise, in the case of
consciousness, we move from ‘I do not introspect that consciousness
is a brain process’ to ‘I introspect that consciousness is not a brain
process’.15
An obvious problem is that the move is far from automatic. There
are many cases where one perceives someone’s body but not their
head (perhaps their head is obscured by someone else’s), but one does
not typically perceive them as headless. Something special is going on
in the headless woman case: rather than simply failing to perceive her
head, one perceives her as headless, and this seeming itself needs to be
explained. Likewise, there are any number of cases where one does
not perceive that some phenomenon is physical, without perceiving
that it is non-physical. I might have no idea how the processes on my
computer are implemented, but they do not seem non-physical in the
way that consciousness does. Likewise, when I introspect my beliefs,
they certainly do not seem physical, but they also do not seem nonphysical in the way that consciousness does. Something special is
going on in the consciousness case: in so far as consciousness seems
non-physical, this seeming itself needs to be explained. Perhaps introspective opacity can play a role in explaining this, but more work is
needed to explain the transition from not seeming physical to seeming
non-physical.
5. Immediate knowledge. A related idea is that a cognitive system
will treat its being in certain states as something it has immediate
 15 Versions of the introspective opacity move can be found in Dennett’s appeal to user
illusions, Drescher’s appeal to ‘gensyms’, Graziano’s appeal to attention schemas,
Tegmark’s appeal to substrate-independence, as well as my own appeal to information
in Chalmers (1990; 1996). An historical precursor is Thomas Hobbes in De Corpore
(1655/1981, section 3.4): ‘The gross errors of certain metaphysicians take their origin
from this; for from the fact that it is possible to consider thinking without considering
body, they infer that there is no need for a thinking body.’ Note that the relevant topicneutral claim is that physical mechanisms are opaque to introspection, not that consciousness itself is opaque to introspection. A non-materialist who endorses the revelation thesis discussed below may accept the first opacity thesis while denying the second.
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24 D.J. CHALMERS
knowledge of, not inferred from or mediated by any other knowledge.
For example, if a computer system with both perceptual and introspective representations says that a green object is present, and one
asks for its reasons, it might naturally answer that it is representing the
presence of a green object. But if one asks for its reasons for saying
that it is representing the presence of a green object, it may well have
no further reasons. The system is simply in that state. It is not given
access to the mechanisms that bring the state about. If the system is a
reasoner that requires reasons for its claims, it will be natural for it to
hold that it has basic or immediate evidence that it is in this state. In
effect, being in these states will at least seem to play a foundational
role for the system, serving both as evidence for introspective judgments (I am in this state) and for further judgments about the world.
Given these special states that seem to be immediately known, it is
natural to think that these will then be represented by the system as
primitive states that it finds itself in.16
Here the familiar problem strikes again: everything I have said
about the case of perception also applies to the case of belief. When a
system introspects its own beliefs, it will typically do so directly,
without access to further reasons for thinking it has those beliefs.
Nevertheless, our beliefs do not generate problem intuitions nearly as
strongly as our phenomenal experiences do. So more is needed to
diagnose what is special about the phenomenal case. At this point
Clark (2000) appeals to the fact that we have direct access to the
sensory modality involved in an experience (seeing rather than
smelling, say), suggesting that this access entails that the subject will
represent an experience as qualitative. However, in the case of belief
we also have access to an attitude (believing rather than desiring, say),
and it is not really clear why access to a modality as opposed to an
attitude should make such a striking difference.
 16 My own proposed solution to the meta-problem in Chalmers (1990; 1996) gave
immediate knowledge a central role. On the story there, introspective opacity naturally
leads to a sense of immediate knowledge, which naturally leads to primitive quality
attribution as below. Clark’s (2000) analysis of the meta-problem builds on this
approach, focusing on immediate access to the sensory modality involved in acts of
detection. Sturgeon (1994) develops a version of the phenomenal concept strategy based
on the idea that phenomenal concepts are concepts of states that serve as their own
evidence. Schwarz (forthcoming) uses introspective opacity to motivate the introduction
of illusory representations of sensory states to play a foundational role in Bayes-style
belief updating.
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THE META-PROBLEM OF CONSCIOUSNESS 25
Perhaps the best response to the belief problem appeals to an idea
closely connected to the immediate knowledge idea: we have a sense
that we are directly acquainted with conscious experiences and with
their objects. It is arguable that this sense of acquaintance is missing
in our immediate knowledge of our beliefs. If so, one could argue that
it is the sense of acquaintance specifically, rather than that of
immediate knowledge more generally, that plays the central role in
generating our puzzlement about consciousness.
There are a couple of distinct elements to the sense of acquaintance.
One is the sense of presentation: that we are somehow immediately
presented with our experiences. Another is the sense of revelation:
that the full nature of consciousness, and of various phenomenal
properties, is fully revealed to us in introspection.17 Both of these may
well play a role in generating problem intuitions. Presentation (which
might be understood as acquaintance with a property instance) is
especially relevant to explaining our certainty that we are having
experiences, and revelation is especially relevant to explaining our
sense that they are irreducible. It remains to provide an explanation of
why we have the sense of presentation and of revelation.
6. Primitive quality attribution. A promising proposal due to Derk
Pereboom (2011) and others picks up on an analogy with the metaproblem of colour: roughly, why do colours seem to be irreducible
qualitative properties? It is common to observe (e.g. Chalmers, 2006)
that vision presents colours as special qualities of objects that are
irreducible to their physical properties. It is also common to observe
that this is an illusion, and that objects do not really have those special
colour qualities. Why, then, do we represent them that way? A natural
suggestion is that it is useful to do so, to mark similarities and differences between objects in a particularly straightforward way. The perceptual system knows little about underlying physical properties, so it
would be hard to represent colours in those terms. Perhaps it could
just represent similarities and differences between objects without
representing specific qualities, but this would be inefficient. Instead,
evolution hit on a natural solution: introduce representations of a
novel set of primitive qualities (colours), and when two objects are
 17 Numerous anti-materialists, such as Goff (2017), have identified a revelation thesis as
the source of their anti-materialism, while numerous materialists, such as Lewis (1995),
have identified a revelation thesis as the central intuition they need to reject.
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26 D.J. CHALMERS
similar with respect to how they affect the relevant parts of visual
system, represent them as having the same qualitative property.18
Nothing here requires that the qualitative properties be instantiated
in the actual world. In fact, nothing really requires that such properties
exist even as universals or as categories. What matters is there seem to
be such qualities, and we represent objects as having those qualities.
(In philosophers’ language, we could represent the qualities de dicto
rather than de re; that is, we could represent that objects have primitive qualities, even if there are no primitive qualities such that we
represent objects as having them.) In the words of Richard Hall
(2007), experienced colours may be dummy properties, introduced to
make the work of perception more straightforward. It is easy enough
to come up with a computational system of colour representation that
works just this way, introducing a representational system that
encodes qualities along an R–G axis, a B–Y axis, and a brightness
axis. Because these axes are represented independently of other
physical dimensions such as spatial dimensions, the corresponding
qualities seem irreducible to physical qualities.
Something like this is plausibly at least part of the solution to the
meta-problem of colour. The idea can be extended to the metaproblem of consciousness by saying that introspection attributes
primitive qualities to mental states for similar reasons. It needs to keep
track of similarities and differences in mental states, but doing so
directly would be inefficient, and it does not have access to underlying
physical states. So it introduces a novel representational system that
encodes mental states as having special qualities. Because these
qualities are represented independently of other physical dimensions
such as spatial dimensions, the corresponding qualities seem
irreducible to physical properties.
This proposal works especially well on a view where phenomenal
properties are (or seem to be) simple non-relational qualities, or
‘qualia’. Such a view might have the resources for explaining why our
problem intuitions differ from our intuitions about belief: sensory
 18 Pereboom’s ‘qualitative inaccuracy’ thesis (2011) is roughly the idea that we misrepresent experiences (like external objects) as having primitive qualitative properties that
they do not have. Versions of the idea that a cognitive system would naturally represent
primitive qualities as a means of representing our own more complex states can be
found in Chalmers (1990; 1996), Dennett (2015), and in Schwarz (forthcoming). Hall
(2007) introduces dummy properties to account for illusions about colours, but does not
apply it to phenomenal properties.
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THE META-PROBLEM OF CONSCIOUSNESS 27
states are represented as simple qualities, while beliefs are represented
as relations to complex contents (the cat is on the mat) that do not
require a novel space of qualities. However, the qualia view is widely
rejected these days, even as an account of how experiences seem to us
introspectively. It is much more common to hold that experiences are
(or seem to be) representational or relational states. For example, the
experience of greenness does not involve a simple ‘green’ quality, but
instead seems to involve awareness of greenness, the colour. Here
greenness is the same quality already used to represent external
objects in perceptual representations, and awareness is a mental
relation, understood as some sort of representation (on a representationalist view) or some sort of perception (on a relational view). On a
view like this, it is unclear how a novel space of primitive qualities
attributed in introspection will enter the picture.
This account also needs to address a crucial disanalogy between the
representation of colours and phenomenal properties. It is typically
easy for people to accept that colours are illusions and are not really
instantiated in the external world, but it is much harder for people to
accept that phenomenal properties are illusions and are not really
instantiated in our minds. This worry is an instance of Kammerer’s
(2018a) ‘illusion meta-problem’, which I will call the resistance problem to avoid confusion: explain why there is so much intuitive
resistance to illusionism.19 Any primitive quality attribution account
will need further ideas to explain the disanalogy.
7. Primitive relation attribution. A closely related idea is that our
introspective models attribute primitive relations to qualities and
contents. Here we can think of a robot that visually senses the world
around it, attends to certain objects, and has introspective representations of its own states. In fact the robot will stand in highly complex
relations to objects and properties in the external world — a complex
 19 Kammerer’s own proposal to solve the resistance problem is that we understand an
illusion of X as a state in which we are affected the same way as in a correct perception
of X, but without the underlying reality. Under those constraints illusionism about the
phenomenal is incoherent, since one of the ways we are affected in a correct perception
of conscious experiences is having conscious experiences. I think this diagnosis can
account for some resistance to illusionism (people do often argue that illusionism is
incoherent in this way), although I think it is easy to formulate understandings of illusions that avoid the problem. In any case, because this diagnosis turns on our concept of
‘illusion’, it cannot account for the fact that we are equally resistant to nearby views that
do not use that concept: for example, the view that we do not have any conscious
experiences. To explain our resistance to views like this, we need to go deeper.
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28 D.J. CHALMERS
causal relation of seeing, an equally complex functional relation of
visual representation, a complex functional relation of attending, and
so on. The robot may not have access to all that complexity, and there
may be little need to model all the details. So it is not unnatural to
suppose that such a system’s introspective models will introduce
primitive relations of seeing, attending, and so on instead. When the
robot sees a red square, instead of representing a complex causal
relation to the red square, the system will model itself as standing in
the primitive relation of seeing to the red square. Likewise, when it is
in the complex state of visually representing a red square (without
being sure whether the square is present), the system may model itself
more simply as standing in a primitive relation of visual experience or
awareness to red squares. The same may go for attention and other
complex cognitive relations.
We can then suppose that this sort of primitive relation attribution is
present in our own introspective models. Perhaps this picture could be
combined with primitive quality attribution grounded in perceptual
models. Then our introspective models represent ourselves as standing
in primitive relations (such as awareness) to primitive qualities (such
as primitive greenness), when our physical states actually involve
complex causal relations to complex physical qualities in the environment. This model might help to explain a number of our problem
intuitions: experiencing a red object will seem relatively simple and
primitive, when the underlying physical reality is complex.
This idea bears a structural resemblance to the key slogan of
Graziano’s attention schema model, according to which ‘awareness is
a model of attention’ (2013). I take Graziano to mean something like:
‘our model of awareness is in fact a simplified model of attention.’
That is, our introspective models represent a simple relation of awareness as a stand-in for the complex relation of attention that is present
in the brain. Graziano does not speak of primitiveness here, and he
says surprisingly little to apply his attention schema model to the
meta-problem.20 Still, his main focus is using a simple mental relation
 20 Early in his book (Graziano, 2013, p. 17) Graziano indicates that he intends the
attention schema model as a way of dissolving the hard problem. ‘The answer may be
that there is no hard problem. The properties of conscious experience — …the feeling,
the vividness, the raw experienceness, and the ethereal nature of it… — these properties
may be explainable as components of a descriptive model.’ After introducing the model,
Graziano occasionally says that the model describes awareness as ‘ethereal’, but he does
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THE META-PROBLEM OF CONSCIOUSNESS 29
(awareness) to model a complex one (attention). One could easily
adapt his slogan to the current context with primitive relation attribution by saying: our model of awareness is a primitive model of complex relations of attention. (Compare: our model of colour qualities is
a primitive model of complex physical reflectance properties.)
Another difference with Graziano is that I am not sure that attention
is the right choice for the complex relation that is being modelled. On
the face of it, perceptual awareness presents itself as a model of all
perception, whether attended or unattended (which is why the idea of
unconscious perception initially strikes us as counter-intuitive). So I
would be inclined to say: our model of perceptual consciousness is a
primitive model of complex relations of perception. More generally,
consciousness presents itself as a model of all mental representation
(which is why the idea of unconscious representation initially strikes
us as counter-intuitive). So I would say: our model of consciousness is
a primitive model of complex relations of representation; or in
Graziano’s simpler terms, consciousness is a model of representation.
The familiar problem of belief still arises. On the face of it, it would
make as much sense to represent a complex belief relation as primitive
too, but we do not find the same problem intuitions. One response
would be to argue that awareness is represented as primitive but belief
is not, perhaps because the functional nature of belief is easier to
represent. Another would be to argue that our strongest problem
intuitions arise from combining primitive relations with primitive
qualities, which happens in the perceptual case but not the belief case.
Perhaps the most promising response is to appeal again to the sense of
acquaintance: the primitive relation attributed in the perceptual case
seems to acquaint us directly with the quality it attributes, and also
itself to be an object of acquaintance, whereas the primitive relation
attributed in the case of belief does not. Kammerer’s resistance problem also arises here: a story needs to be told about why we find it
much harder to deny that primitive mental relations are instantiated
than that primitive external qualities are instantiated.
I move now to extant ideas about the meta-problem that I am less
inclined to endorse.
8. Introjection and the phenomenological fallacy. U.T. Place (1956)
diagnoses resistance to materialism as lying in the phenomenological
 physical. It should also be noted that Graziano (2016) resists describing his view as
illusionist.
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30 D.J. CHALMERS
fallacy: ‘the mistake of supposing that when the subject describes his
experience, when he describes how things look, sound, smell, taste, or
feel to him, he is describing the literal properties of objects and events
on a peculiar sort of internal cinema or television screen.’ The
phenomenological fallacy is closely related to the traditional sensedatum fallacy: the idea that when we have an experience of a red
square there must be some sort of internal red square sense-datum of
which we are aware. If there were such sense-data, they would be hard
to physically explain, so the fallacy (if we commit it) provides a
potential explanation of problem intuitions.
An obvious objection is that many people explicitly reject the sensedatum fallacy, but their problem intuitions remain as strong as ever.
On the face of it, an experience as of a red square raises the hard problem whether or not anything is red or square. Even if one is a representationalist who holds that one’s experiences represent a red square
that may not exist, or a naïve realist who holds that the experience is a
direct perception of a red square in the external world, the hard problem seems as hard as ever. Why should the physical processes associated with perception and representation yield any experience at all?
Perhaps Place could argue those who ask this question are still in the
grip of the fallacy despite explicitly rejecting it. But I think it is more
plausible that he has misdiagnosed the roots of our problem intuitions.
The phenomenological fallacy is an instance of what Richard
Avenarius (1891) called ‘introjection’: roughly, perceiving something
outside the head as being inside the head. Introjection has been used in
various other ways to deflate problem intuitions. Frank Jackson (2003)
suggests that we mistake intensional properties (e.g. experiences’
representing redness) for instantiated properties (e.g. experiences’
being red). Instantiated phenomenal properties would give rise to a
hard problem, but mere representations of them do not. David
Rosenthal (1999) suggests that when we ‘relocate’ perceived qualities
in the mind, we falsely infer that these qualities must always be
conscious. These moves are perhaps most promising for deflating the
explanatory gap tied to qualities such as redness: if these qualities are
merely represented or can occur unconsciously, they pose less of a
gap. As before, however, the core of the hard problem is posed not by
the qualities themselves but by our experience of these qualities:
roughly, the distinctive phenomenal way in which we represent the
qualities or are conscious of them. Recognizing the introjective fallacy
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THE META-PROBLEM OF CONSCIOUSNESS 31
for qualities does little to deflate the problem of explaining our experience of them.21
9. The user illusion. The centrepiece of Daniel Dennett’s illusionism
in recent years has been the claim that consciousness is a ‘user illusion’, analogous to illusions generated when the user of a computer
interacts with icons on a computer screen. The rough idea is that the
icons provide a convenient way of representing the computer screen
that greatly oversimplifies or falsifies the underlying reality: for
example, there is not literally a folder anywhere in the computer. This
is a nice statement of introspective-model illusionism, but as it stands
it does not provide much guidance on the specific mechanisms of how
the illusion of consciousness is generated.22
What is Dennett’s account of problem intuitions? An overarching
account is hard to find. Instead, he has appealed to a collection of
ideas over the years, most of which are discussed elsewhere on this
list.23 One distinctive thesis is that the user illusion arose to facilitate
communication, which he thinks is the most important use for selfmonitoring. There are elements of introspective opacity in Dennett’s
repeated stress on the idea that we lack access to the details that
underpin our representations. There are elements of primitive quality
attribution in his account of how we project apparently simple
properties like sweetness and redness onto the world. There are
elements of the phenomenological-fallacy idea in his account of why
we take it that if there is no red stripe in the world, there must be a red
stripe in our mind. We have seen that all of these have limitations as
accounts of problem intuitions, and Dennett’s account is subject to the
same limitations.
 21 Jackson and Rosenthal go on to try to explain conscious experience of these qualities in
terms of distinctive functional manners of representation (Jackson) and higher-order
thoughts (Rosenthal). These moves give rise to familiar explanatory gaps which need
further tools to diagnose or deflate. In a somewhat related strategy, Byrne (2006)
suggests that we have mislocated the source of the problem: there is a hard problem of
colour but no hard problem of consciousness (he deflates the latter by arguing that the
transparency of experience suggests that we have no access to the nature of experience).
22 Tor Norretranders’ (1991) book The User Illusion: Cutting Consciousness Down to
Size, which Dennett credits for the phrase, does not help much. Norretranders is mostly
concerned with illusions about the self and about free will, and in particular the illusion
that the conscious self is in control of our actions. He does not really try to argue that
consciousness in general is an illusion.
23 For useful recent summaries, see ‘Why and How Does Consciousness Seem the Way it
Seems?’ (Dennett, 2015), and chapter 14 of From Bacteria to Bach and Back (Dennett,
2017).
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10. The use-mention fallacy. Advocates of the phenomenal concept
strategy sometimes suggest that because thinking about consciousness
is so different from thinking about brain states, we illegitimately infer
that consciousness cannot be a brain state. This is a sort of usemention error, since it involves mistaking a difference in our representations of an object for a difference in the object. In developing this
idea, Loar (1990), Tye (1999), and Papineau (2002) all stress the fact
that deploying a phenomenal concept itself has a sensory or imagistic
phenomenology which is not involved in deploying a physical
concept.24
This strategy requires a serious lack of charity concerning philosophers who have problem intuitions, as philosophers usually avoid usemention errors like this quite easily. As Sundstrom (2008) points out
in critiquing Papineau’s discussion of the fallacy (which he calls the
‘antipathetic fallacy’), the strategy also over-generates to falsely
suggest that we should not accept all sorts of identities that we in fact
accept, such as my ‘pain is my brother’s least favourite state’.25 So I
am inclined to set this strategy aside as one of the least promising
explanations.
11. Underestimating the physical. It is sometimes suggested that we
are only impressed by the mind–body problem because we underestimate the body. That is, we have an overly thin conception of the
physical, and that with a more adequate conception the mental–
physical gap may disappear. One version of this view (e.g. Stoljar,
2001; Strawson, 2006) holds that we conceive of the physical in
structural terms (perhaps in terms of the equations of physics),
ignoring its intrinsic nature, which may have a close tie to consciousness. This path often leads to panpsychism and Russellian monism.
I agree that a structural conception of the physical is partly
responsible for problem intuitions involving a gap between physical
processes and consciousness. That said, there are many problem
intuitions that do not take this form. For example, the key intuition in
setting up the hard problem is that explaining functions does not
explain consciousness. These intuitions concern the phenomenal
 24 The ‘stereoscopic fallacy’ of Lycan (1987, p. 76) is a perceptual variant on this idea:
seeing the brain of someone seeing red is not like seeing red, so seeing red is not a brain
state.
25 Papineau (2011) responds to Sundstrom, and Kammerer (2018b) responds in turn to
Papineau. Kammerer (ms) gives a general critique of the idea that the explanatory gap
arises from a fallacy of reasoning or a cognitive illusion.
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THE META-PROBLEM OF CONSCIOUSNESS 33
rather than the physical and are not removed by enriching our
conception of the physical. Explaining these intuitions at the heart of
the meta-problem will require some other strategy.
12. Historical and cultural explanations. In principle, any
synchronic explanation of the processes responsible for problem
intuitions will be enriched by a historical explanation of how and why
the processes came to be that way. Among historical explanations, I
have so far mostly focused on evolutionary design explanations,
where a mechanism connected to problem intuitions (e.g. introspective
models or primitive quality attribution) follows from some sensible
design choice in a cognitive system. I have also touched on Dennett’s
evolutionary explanations that tie consciousness to communication.
Others have suggested that dualist intuitions arise from underlying
psychological drives, such as the fear of death and the desire for
survival. Nicholas Humphrey (2006) inverts this sort of explanation,
suggesting that mind–body dualism and our sense that we are conscious give us a conviction that we have something special to preserve
in ourselves and our children, thereby enhancing the drive for survival
and reproduction.
Historical explanations in terms of culture are also available. Some
might give genealogical accounts of problem intuitions in terms of
accidents of cultural history. Perhaps we have all been over-influenced
by Descartes, for example, or misled by certain English-language constructions. My own working assumption is that, while cultural factors
and psychological drives certainly play a role in shaping phenomenal
intuitions, the underlying basis of these intuitions runs deeper. I think
that evolutionary design explanations are potentially the most powerful historical explanations here, but a wide variety of historical and
cultural explanations are worth considering.
13. Other proposals. There are a number of further potential solutions to the meta-problem that I have not discussed. Humphrey (2011)
proposes (in addition to his historical explanation mentioned above)
that self-sustaining re-entrant feedback loops involving internal states
in a high-dimensional space give rise to the ‘illusion of extraordinary
otherworldly properties’. Fiala, Arico and Nichols (2011) suggest that
problem intuitions may arise from conflicting verdicts about consciousness from our fast (automatic) system and our slow (controlled)
system in a dual-systems model. Molyneux (2012) argues that a robot
would inevitably have problem intuitions due to a regress in making
subjective–objective identifications. Drescher (2006) suggests (in
addition to his ‘gensym’ explanation of qualia intuitions mentioned
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above) that a ‘Cartesian camcorder’ higher-order monitoring system
explains why consciousness seems like an intrinsic property of mental
events. I am sceptical about each of these proposed solutions for fairly
predictable reasons, but I will not discuss the reasons here.
Summary. To sum up what I see as the most promising approach:
We have introspective models deploying introspective concepts
of our internal states that are largely independent of our physical
concepts. These concepts are introspectively opaque, not revealing any of the underlying physical or computational mechanisms.
Our perceptual models perceptually attribute primitive perceptual
qualities to the world, and our introspective models attribute
primitive mental relations to those qualities. We seem to have
immediate knowledge that we stand in these primitive mental
relations to primitive qualities, and we have the sense of being
acquainted with them.
I hope that something like this is simultaneously (i) a reasonably
plausible picture of how consciousness seems to us introspectively,
and (ii) a reasonably well-motivated picture of how a well-designed
cognitive system might represent its own states to itself. The
characterization is neutral between realism and illusionism. A realist
can take it as a picture of how genuine consciousness seems to us
introspectively. An illusionist can take it as a picture of the illusion of
consciousness. Either way, this approach might take us some distance
toward a solution to the meta-problem of explaining our problem
phenomenal intuitions in topic-neutral terms. Certainly this account is
not a complete account. In some respects it is closer to a fleshed-out
explanandum (what needs to be explained) than an explanans (a substantial explanation). Still, an analysis like this is at least a start.
Ideally, potential solutions to the meta-problem can be tested both
experimentally and with computational models. Experimentally, we
can investigate human problem intuitions to see how well they conform to what a given proposal predicts. As discussed in the previous
section, there is a small body of relevant experimental work as things
stand. There is certainly room for much more work here, in principle
yielding a serious research programme in experimental philosophy
and experimental psychology.
Computationally, we can build computational models that build in
versions of the proposed mechanisms, and we can see whether these
models reproduce something along the lines of human phenomenal
reports. The only work along these lines that I know of is by Luke
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Muehlhauser and Buck Shlegeris, summarized by Muehlhauser
(2017). They build a simple software agent using a theorem prover,
based on principles that they attribute to Chalmers (1990; 1996) and
Kammerer (2016). The system produces some simple reports that are
structurally analogous to human phenomenal reports in certain
respects. This is a very simple system with obvious limitations, but it
suggests a research programme. Using principled underlying mechanisms, we can attempt to build increasingly sophisticated system that
exhibit human-like phenomenal reports with increasing scope and
accuracy. If it is possible to build a reasonably accurate system of this
sort, the mechanisms it uses will provide a candidate solution to the
meta-problem.26
3. The Meta-Problem Challenge
for Theories of Consciousness
The hard problem of consciousness and the meta-problem are closely
connected. If we had a solution to the hard problem, we would expect
it to shed some light on the meta-problem. In reverse, if we had a
solution to the meta-problem, we should expect it to shed some light
on the hard problem.
Illusionism provides one way in which the meta-problem could shed
light on the hard problem. Illusionists think that a solution to the metaproblem will dissolve the hard problem. I will discuss this sort of
illusionist strategy in the next section. For now, I will focus on consequences of the meta-problem for non-illusionist theories of consciousness according to which consciousness is real.
A plausible connection between the hard problem and the metaproblem for non-illusionist theories runs as follows. Whatever
explains consciousness (the hard problem) should also play a central
role in explaining our judgments about consciousness (the meta-
 26 Computational models such as these may bear on the occasionally-discussed idea of
using phenomenal reports as a test for machine consciousness: roughly, if a machine
behaves as if it is puzzled about consciousness, that is reason to think it is conscious.
Versions of this idea include Sloman’s ‘demanding new Turing test for robot philosophers’ (2007), Argonov’s ‘non-Turing test’ for machine consciousness (2014), and
Schneider and Turner’s ‘artificial consciousness test’ (2017). The Muehlhauser/
Shlegeris system mirrors at least some aspects of our phenomenal reports, while being
so simple that most people would deny that it is conscious. If this pattern continues with
more developed computational approaches to the meta-problem, then we should probably be cautious about this sort of test for machine consciousness.
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problem). That is, suppose there is a correct non-illusionist theory of
consciousness according to which mechanism M is the basis of consciousness. Then we can reasonably expect that mechanism M plays a
central role in explaining our judgments about consciousness.
The reasoning here is simple: consciousness and judgments about
consciousness are closely connected. For a realist, judgments about
consciousness systematically reflect the character of consciousness. It
would be extremely strange if the mechanisms responsible for consciousness played no role, or only a minimal role, in generating judgments about consciousness. These mechanisms may not wholly
explain our judgments. It is plausible that some further introspective
processes beyond consciousness itself are required to generate the
judgment. Still, a realist should expect that our judgments about consciousness are the way they are because consciousness is the way it is,
or at least because the basis of consciousness is the way it is. So the
mechanisms responsible for consciousness should play a central role
in generating judgments about consciousness.27
This provides what we might call the meta-problem challenge for
theories of consciousness. If a theory says that mechanism M is the
basis of consciousness, then it needs to explain how mechanism M
plays a central role in bringing about judgments about consciousness.28
We can apply this challenge to existing theories. For example,
according to integrated information theory (Tononi, 2007), integrated
information is the basis of consciousness. Our principle then suggests
that integrated information should play a central role in explaining
judgments about consciousness. The meta-problem challenge asks:
 27 Why not say more straightforwardly: consciousness should play a central role in generating judgments about consciousness? I do this in part because many of these theories
leave the metaphysical relationship between consciousness and the underlying mechanisms somewhat unclear: for example, there are versions of IIT and GWT that are consistent with materialism, dualism, and epiphenomenalism. These issues about the metaphysical status and causal role of consciousness are addressed in the following sections.
In this section I am focusing on a more metaphysically neutral issue concerning mechanisms that arises even if consciousness is distinct from the underlying mechanisms.
28 The meta-problem challenge is closely related to the ‘coherence test’ for theories of
consciousness in Chalmers (1990): ‘A completed theory of mind must provide (C1) An
account of why we are conscious. (C2) An account of why we claim to be conscious;
why we think we are conscious. Further (C3), accounts (C1) and (C2) must cohere with
each other.’
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how does integrated information explain judgments about
consciousness?
The answer is far from obvious. On the face of it there is no obvious
link between integration of information and these judgments. In fact,
according to IIT, for every system with high integrated information
there will be a computationally isomorphic simulated system with
zero integrated information. The simulated system will be behaviourally identical to the original systems, making the same reports as we
understand them, and more generally will be functionally identical,
having the same intuitions. It is arguable that there is a computational
explanation of the intuitions that applies equally to both the high-phi
system and the zero-phi system. It is also not clear why high-phi
systems (e.g. those with strongly integrated sensory modalities) should
be more likely to make the reports than intermediate-phi systems (e.g.
those with weakly integrated sensory modalities). If so, it looks as if
high integrated information plays no essential role in explaining
phenomenal intuitions. If that is right, then it provides at least some
reason to doubt whether integrated information is the basis of
consciousness.
Of course this is not a knockdown argument against IIT, and there
are various ways in which an IIT advocate might respond. But it provides at least a prima facie challenge for IIT to address. A similar
challenge arises for biological theories of consciousness (e.g. Block,
2009) that allow that there could be functional duplicates of conscious
beings (made of silicon, for example) that are not conscious. As with
IIT, these duplicates will share our intuitions, and it looks as if
specifically biological mechanisms will not play an essential role in
explaining the intuitions.29
One could apply the same challenge to global workspace theories
(Baars, 1988), according to which the basis of consciousness is a
global workspace that makes information available to other systems in
the brain. Here the challenge asks: how does the global workspace
help to explain our judgments about consciousness? A version of the
same challenge applies to many first-order representationalist theories
 29 One response for the advocate of these theories is to advocate a version of the realizationism discussed in the next section: mechanism M is not necessary for the reports but,
at least in systems with M, M causes the reports. Perhaps this will work for biological
theories, but in the case of IIT it is far from obvious how high phi even causes the
reports. These theories will also have to say something about the problems for realizationism discussed below.
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of consciousness (e.g. Dretske, 1995), which typically hold that conscious states are those representational states that are globally available or that are poised for the control of action and reasoning in some
way.
Global workspace and first-order representational theories can at
least begin to answer the challenge. For example, it is plausible that
information is only reported at all if it is globally available, giving an
initial connection between the workspace and reports. Still, it is not
obvious how the workspace explains problem reports involving a
sense that consciousness is puzzling. So there is at least more for a
workspace theorist or a first-order representationalist to say here.
Higher-order thought theories (Rosenthal, 2002) say that conscious
states are those that are the objects of higher-order thoughts. Here the
meta-problem challenge asks: how do higher-order thoughts explain
problem reports? Now, of course higher-order thoughts are involved
in any introspective process, so they play a central role in explaining
how we explain any mental states. But as Alvin Goldman (2000)
pointed out, it is not clear how mere higher-order thoughts explain
why we report mental states as being conscious (prima facie, that
requires having higher-order thoughts about higher-order thoughts),
and likewise it is not obvious how higher-order thoughts explain why
we report conscious states as puzzling. So again there is a challenge to
answer here.30
We can apply a similar challenge to all sorts of theories. Consider
quantum theories (Hameroff and Penrose, 1996; Stapp, 1993) that say
there is a strong tie between wave-function collapse and consciousness. Does wave-function collapse play a central role in explaining
reports of consciousness? One might worry that the answer is no,
since wave-function collapse only selects one of multiple branches of
the wave function. If a subject says ‘I am conscious’ in the selected
branch, it is arguable that the subject also says ‘I am conscious’ in
 30 An interesting variant of higher-order thought theory that is driven by the meta-problem
is primitive higher-order thought theory, which says that conscious states are the objects
of primitive higher-order thoughts. A primitive higher-order thought is one that attributes primitive qualities and/or relations to a lower-order state, as in the primitive
quality/relation accounts discussed earlier. Another version is dispositional primitive
higher-order thought theory, on which a mental state is conscious if it is disposed to
bring about primitive higher-order thoughts. These views are closely related to the
versions of weak illusionism discussed later.
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THE META-PROBLEM OF CONSCIOUSNESS 39
many unselected branches. If so it looks as if there may be an
explanation of the reports which is prior to wave-function collapse.
The challenge even applies to panpsychist theories (e.g. Brüntrup
and Jaskolla, 2017). These theories typically hold that human consciousness is some sort of combination of micro-consciousnesses in
fundamental entities. The combination problem for panpsychism is to
explain how micro-consciousnesses can combine to yield our consciousness. In light of the meta-problem challenge, there is a further
aspect of the combination problem: explain how these combination
states play a central role in bringing about reports of consciousness.
One philosophical theory that has an especially hard time meeting
the meta-problem challenge is analytic functionalism (e.g. Armstrong,
1968b), according to which all of our mental concepts, including our
concepts of consciousness, are functional concepts (concepts playing
certain functional roles, such as discrimination, integration, report, and
the like). Nagel (1970) pointed out that Armstrong’s analytic functionalism ‘leaves it a complete mystery why [the problem of other minds]
has ever bothered anyone’. If analytic functionalism is right, the problem of other minds is conceptually equivalent to the problem of knowing that others have the relevant functional states, which does not
bother us in the same way. Nagel’s point applies equally to the mind–
body problem. If analytic functionalism were true, the hard problem
would be conceptually equivalent to the easy problems, and prima
facie we would not be any more bothered by the hard problem than by
the easy problems. As a result, analytic functionalism seems to be
psychologically inadequate in addressing the meta-problem.
What sort of realist theory of consciousness does especially well
where the meta-problem challenge is concerned? My own tentative
view is that the most promising solution to the meta-problem lies in
primitive relation attribution and the sense of acquaintance: our
experiences seem to primitively acquaint us with qualities in the
environment, and these experiences are themselves objects of
acquaintance. I favour a realist theory of consciousness where consciousness does in fact involve acquaintance in this way. This line
tends to suggest a combination of a first-order representational view of
consciousness (consciousness involves immediate awareness of
worldly properties) with a self-representational view of consciousness
(consciousness involves immediate awareness of itself).
I do not think this sort of awareness is reducible to brain mechanisms, but one might expect some sort of corresponding structure at
the level of brain mechanisms. To speculate: one might expect a
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corresponding structure of first-order representational states that are
themselves objects of a simple sort of representation, or that are at
least disposed to be objects of representation. Such a view could be
developed in a higher-order way, perhaps bringing in a version of the
dispositional primitive higher-order thought view mentioned earlier.
My own inclination would be to develop this view in a first-order
way, by finding a first-order property F that grounds the higher-order
representation. First-order states with F will be disposed to be objects
of primitive higher-order representation (in the presence of appropriate introspective systems), but can also exist without any higherorder representation (in the absence of appropriate introspective
systems). If there is such a first-order property F, it would play a key
role in solving the meta-problem and would be a strong candidate to
be the physical basis of consciousness itself. The residual question is
then to find out just what property this might be.31
4. Six Reactions to the Meta-Problem
I now step back from specific theories of consciousness and specific
solutions to the meta-problem to think about the issues at a greater
level of generality, looking at general metaphysical options that arise
in light of the meta-problem.
Let us say that the meta-problem processes are the topic-neutrally
characterized processes that explain phenomenal intuitions. For concreteness it may help to think of the meta-problem processes along the
lines above: they involve higher-order models with introspective concepts that attribute special mental states (such as primitive relations to
primitive qualities) to ourselves when our brains are in certain lowerorder cognitive states (such as perception, attention, or access consciousness, characterized topic-neutrally). I will call these lower-order
cognitive states that drive the meta-problem lower-order metaproblem states (Frankish, 2016, calls them ‘quasi-phenomenal’ states,
as these are the states that are misrepresented as phenomenal), and I
 31 In ‘Consciousness and Cognition’ (1990) and The Conscious Mind (1996), I argued in
effect that any first-order informational state could play this role in grounding primitive
higher-order representations (in the presence of appropriate introspective systems). That
is, any informational state might seem to an introspecting subject to be a primitive
qualitative state. If so, the property of being informational would be the key to the metaproblem and a potential basis of consciousness. An obvious objection arises from the
case of belief, however, which suggests that more constraints may be required.
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will call the introspective states that attribute primitive properties
higher-order meta-problem states.
We can then ask: if there is a solution to the meta-problem,
involving meta-problem processes, what is the relationship between
consciousness (that is, phenomenal consciousness, or subjective
experience) and the meta-problem processes? A number of views are
possible. I will discuss three broadly non-reductionist reactions, which
need not involve any element of illusionism, and three broadly
reductionist reactions, each with an element of illusionism.
1. There is no solution to the meta-problem. Some non-reductionists
may embrace meta-problem nihilism: there is no solution to the metaproblem. Alternatively, if we understand the meta-problem more
broadly as ‘Explain our problem intuitions in topic-neutral terms, or
explain why this is impossible’, then the meta-problem nihilist says
that any solution must take the second horn. As discussed earlier, a
version of this view might be taken by anomalous dualists and anomalous materialists for whom behaviour and/or the causal role of consciousness cannot be systematized in topic-neutral terms. It is far from
clear how this would work, but there is at least room to investigate the
possibility.
2. Consciousness correlates with the meta-problem processes. A
second non-reductionist view is meta-problem correlationism, on
which consciousness plays no causal role in the meta-problem processes, but it correlates with those processes. At least typically, when
there is a phenomenal intuition generated by a first-order nonphenomenal state, there is a corresponding phenomenal state that
renders the phenomenal intuition largely correct. On one version of
the view, the phenomenal state will be present only when the phenomenal intuition (or some meta-problem process) is present, while on
another view (preferable, I think) the phenomenal state will correlate
with first-order states whether or not the meta-problem process is
present.
An obvious problem for this view, to be discussed in more depth
shortly, is that it seems to make our phenomenal intuitions correct as a
matter of luck. If consciousness plays no role in generating the
intuitions, it seems to be at best a coincidence that they are correct at
all. A proponent of this view might respond by finding a deep underlying principle connecting first-order states to phenomenal states that
makes the connection more than a coincidence. But as usual, there is
work to be done.
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3. Consciousness realizes the meta-problem processes. A third view
available to non-reductionists is meta-problem realizationism, on
which consciousness plays a role in realizing meta-problem processes.
We saw earlier that theorists may hold that a topic-neutral explanation
of phenomenal beliefs is correct but not complete, because consciousness realizes some of those processes, thereby playing a causal role
with respect to their outcome. Perhaps panpsychist consciousness
plays a role in physical dynamics. Perhaps interactionist consciousness plays a role in high-level dynamics. Meta-problem realizationism
is also available to some reductionists. For example, some biological
materialists may hold that consciousness is essentially biological and
realizes computational processes that generate phenomenal intuitions.
Likewise, some quantum-mechanical materialists may hold that
consciousness is a quantum process that realizes the meta-problem
processes.
On one version of the realizationist view to which I have some
attraction, phenomenal consciousness realizes access consciousness.
That is, wherever there is access consciousness functionally characterized, it is actually phenomenal consciousness that does the underlying
causal work, either via the interactionist model or via the pan(proto)-
psychist model. This way phenomenal consciousness would serve as
the basic cause of the processes that generate our phenomenal
intuitions. At the same time, pictures of this sort have many
challenges. It is by no means straightforward to see how consciousness could play precisely the role required, either on a panpsychist or
an interactionist picture (or even on a biological or quantum picture).
But there is at least room to investigate this sort of possibility.
If realizationism is true, consciousness will not be causally
irrelevant to our problem intuitions. Rather, consciousness will be a
primary cause of those intuitions. More deeply, consciousness may be
causally responsible for some key meta-problem processes. For
example, our introspective models representing primitive properties
may themselves be causally grounded in the presence of primitive
properties of consciousness. These models of consciousness may also
usefully serve as a simplified model of more complex physical processes of perception, attention, and representation, but consciousness
itself will play a key role in the models. One may still worry about
whether it plays a central enough role, not least because the structure
of the processes may seem to explain our intuitions even without consciousness, but this view gives at least a promising start in integrating
consciousness with the meta-problem processes.
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4. Phenomenal consciousness does not exist. The first reductionist
view is strong illusionism, which holds that consciousness itself is an
illusion and does not exist. On the most obvious version of this view,
consciousness is identified with the special primitive properties that
are (or seem to be) attributed by our introspective models. No such
special primitive properties are instantiated in our brains, so phenomenal consciousness does not exist. Our sense of being phenomenally
conscious is an illusion.
5. Consciousness is a lower-order meta-problem state. On this
view, phenomenal consciousness is identified with the cognitive states
such as perception, attention, and access consciousness that serve as
the original target of the meta-problem processes. One might justify
the view this way: (1) phenomenal consciousness is what our introspective models are modelling, (2) these introspective models are
really modelling access consciousness (albeit imperfectly), so (3)
phenomenal consciousness is really access consciousness (or perception, attention, or whatever).
This view will probably be a form of weak illusionism, on which
phenomenal consciousness exists but some of our intuitions about it
are illusions. For example, dualist and primitivist intuitions (consciousness is primitive and non-physical) will be incorrect on this
model, as will explanatory intuitions (consciousness cannot be
physically explained). Depending on how the view is developed, the
same may or may not be true for knowledge and conceivability
intuitions.
6. Consciousness is a higher-order meta-problem state. On this
view, consciousness is identified with certain meta-problem processes
that attribute special states to ourselves. On this view, only creatures
with certain introspective models will be phenomenally conscious.
One might justify the view this way: (1) phenomenal consciousness is
the sense of being in special states, (2) this sense is identical to certain
meta-problem states, so (3) phenomenal consciousness is certain
meta-problem states.
This view will also lead to a sort of weak illusionism where at least
our metaphysical and explanatory intuitions are false. It shares something in common with higher-order theories of consciousness, in that
consciousness will involve certain higher-order representations of
lower-order states. One obvious problem with this view is that it
seems to involve a level confusion: on the face of it, consciousness is
what our introspective models described earlier are about. But perhaps
there is room for some terminological revisionism here.
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Which of these six options is best? I will explore this in the
following sections by first discussing two ways of leveraging the
meta-problem into an argument for illusionism. This both clarifies the
case for illusionism and also clarifies the best views for a nonreductionist to take in response to the meta-problem. After that I will
discuss the best views for an illusionist. To telegraph my conclusions,
I think the most important views here are realizationism (for the nonreductionist) and strong illusionism (for the reductionist).
5. Debunking Arguments for Illusionism
The meta-problem can be leveraged into an argument for illusionism
via a debunking argument. A debunking argument is roughly an argument that starts from a premise about how beliefs about a domain are
formed and concludes that beliefs in that domain are not justified or
reliable. For example, Richard Joyce (2006) argues from the claim
that moral beliefs are formed because of evolutionary pressures to the
conclusion that moral beliefs are not justified. Sometimes a debunking
argument argues against certain theories in a domain by making a case
that if those theories are true, beliefs in that domain are not justified or
reliable. For example, Sharon Street (2006) uses an evolutionary
analysis of moral beliefs to argue against moral realism, on the
grounds that if moral realism were true, our moral beliefs would be
unreliable.32
In the case of consciousness, one could make a debunking argument
against non-reductionist views of consciousness, as follows: if there is
a broadly reductionist explanation of our non-reductionist beliefs
 32 As far as I know, there has not been much explicit formulation and discussion of
general debunking arguments regarding consciousness. Many illusionists endorse both
the premises and conclusions of debunking arguments, but they have not focused on
arguments from the premises to the conclusions. Some theorists have tried to debunk
specific theoretical beliefs about consciousness (e.g. materialists debunking beliefs in
dualism) without debunking beliefs about consciousness in general. One relevant
general argument is formulated by Sydney Shoemaker in ‘Functionalism and Qualia’
(1975). Shoemaker argues for functionalism by arguing that if non-conscious functional
duplicates of us with the same beliefs were possible, we could not know we are conscious. Shoemaker’s premises concern possibility (e.g. the possibility of absent qualia)
or about causation (consciousness plays no relevant causal role) rather than explanation,
but there is at least a flavour of debunking. In The Conscious Mind (1996, pp. 192–3)
and in ‘The Content and Epistemology of Phenomenal Belief’ (2003), I formulate and
reply to related debunking arguments that bring in an underlying premise about the
explanatory irrelevance of consciousness. I am interested to hear of other sources, both
recent and historical.
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THE META-PROBLEM OF CONSCIOUSNESS 45
about consciousness (as the meta-problem may suggest), nonreductionist beliefs will not be justified. In effect, the reductionist
explanation of non-reductionist beliefs debunks our reasons to think
that non-reductionist beliefs are correct.
One can also make a debunking argument about beliefs about
phenomenal consciousness in general, perhaps with some variety of
non-reductionism operating as a background assumption. There are
various ways to lay out such an argument, but perhaps the most
straightforward is as follows:
1. There is a correct explanation of our beliefs about consciousness that is independent of consciousness.
2. If there is a correct explanation of our beliefs about consciousness that is independent of consciousness, those beliefs are not
justified.
_______________
3. Our beliefs about consciousness are not justified.
Premise 1 is close to the claim that there is a topic-neutral explanation
of our phenomenal intuitions, although there is a little daylight
between the two. Premise 2 is an instance of a general debunking
principle: if there is an explanation of our beliefs about X that is
independent of X, those beliefs are not justified. (Of course much
depends on what ‘independent’ means; I will return to that matter
shortly.) The conclusion is not exactly a statement of illusionism but,
once it is accepted, illusionism is a natural consequence.
The argument is roughly analogous to debunking arguments that
have been offered about God and morality. Debunking arguments
about God argue that there is an explanation for beliefs in God that is
independent of any gods, and use this to argue that our beliefs in God
are unjustified. Debunking arguments about morality argue that there
is an explanation for our moral beliefs that is independent of any
objective moral truths, and use this to argue that our beliefs in
objective moral truths are unjustified. Some principle like this is at
work in the debunking arguments about God and morality mentioned
above. One backing idea is that if the explanation of our beliefs about
X is independent of X, then our beliefs about X will themselves be
independent of X. If so, it will be entirely a matter of luck whether
those beliefs are correct, so that the beliefs are not justified. Of course
there is much to say about arguments of this form, about the underlying debunking principles, and about the precise sense of ‘independent’ that might make the premises true.
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What can a non-reductionist say in response? Some may reject
premise 1 on the grounds that there is no solution to the metaproblem. I am not inclined to reject the argument on these grounds,
but there are at least three other ways in which the argument can be
rejected.
First, regarding premise 1: if there is a solution to the meta-problem,
it follows that there is a topic-neutral explanation of phenomenal
intuitions, but it does not follow that there is a topic-neutral explanation of phenomenal beliefs. I argued in Chalmers (2003) that consciousness plays a constitutive role in phenomenal beliefs (which are
the objects of justification), so the explanation of those beliefs is not
independent of consciousness. And it is phenomenal beliefs, not
intuitions, that are objects of justification.
Second, regarding premise 2: this arguably requires something like a
causal account of justification, which is far from obvious where consciousness is concerned. On the view that I developed in The Conscious Mind, beliefs about consciousness are justified by our
immediate acquaintance with consciousness, not by any causal background. As long as meta-problem processes do not undermine that
acquaintance, they do not undermine our justification. So even if there
is a causal explanation of our beliefs about consciousness in which
consciousness plays no role, those beliefs may still be justified.
Third, regarding both premises: one can argue that there is a sense
of ‘independent’ in which premise 1 is true and a sense in which
premise 2 is true, but these are different senses. The sense in which
premise 1 follows simply from a solution to the meta-problem is what
we might call descriptive independence: the explanation doesn’t
mention consciousness. If one endorses the possibility of zombies (a
further non-reductionist commitment), we also have modal independence: the elements of the explanation could obtain without consciousness. However, descriptive and modal independence do not make
premise 2 plausible. There are brain-based explanations of our beliefs
about tables that do not mention tables, and that could occur in the
absence of tables, but as long as tables in fact cause the beliefs, the
beliefs seem well-enough grounded in tables to avoid debunking.
Similarly, there are physics-based explanations of our beliefs about
tables that do not mention tables, but as long as the physical processes
in question constitute tables, this descriptive independence does not
debunk table beliefs. To be plausible, premise 2 requires something
more: perhaps a combination of causal independence (consciousness
plays no causal role in the processes invoked in the explanation) and
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constitutive independence (consciousness does not constitute and is
not constituted by elements of the explanation).
A solution to the meta-problem does not guarantee an explanation of
phenomenal beliefs that is causally and constitutively independent of
consciousness. In the first response above I have already mentioned
one way in which consciousness may play a constitutive role in the
explanation: consciousness may constitute phenomenal beliefs themselves. Furthermore, on the realizationist view discussed in the last
section, consciousness will play a causal role in meta-problem processes. If so, then we do not have any sense of ‘independent’ on which
premise 1 follows from a solution to the meta-problem (and/or nonreductionism) and in which premise 2 is plausible, so the argument
does not go through.
I think any of these replies can block the debunking argument. Still,
there unquestionably remains some discomfort in the vicinity. On all
these views, it seems that at least an uncomfortably large part of the
formation of our phenomenal beliefs can be explained without any
role for consciousness, yielding a strange coincidence between our
phenomenal intuitions and consciousness itself. One might use this
discomfort to mount a related coincidence argument for illusionism.
1. There is an explanation of our phenomenal intuitions that is
independent of consciousness.
2. If there is an explanation of our phenomenal intuitions that is
independent of consciousness, and our phenomenal intuitions
are correct, their correctness is a coincidence.
3. The correctness of phenomenal intuitions is not a coincidence.
_________________
4. Our phenomenal intuitions are not correct.
Because this argument concerns phenomenal intuitions (rather than
beliefs) and concerns coincidence (rather than justification), the first
and second objections to the previous argument do not really get a
grip here. Premise 1 now just says that there is a solution to the metaproblem (at least if independence is understood as descriptive
independence), and premises 2 and 3 have some prima facie plausibility. As before, though, much depends on what is meant by
‘independent’, and a version of the third objection may apply.
As before, a solution to the meta-problem guarantees only
descriptive independence and perhaps modal independence in premise
1, while the case of tables suggests that these varieties of independence are not enough to justify premise 2. As long as we have causal or
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constitutive dependence of phenomenal intuitions on consciousness,
the sense of coincidence may be removed. As before a realizationist
might argue that consciousness plays a causal role in explaining
phenomenal intuitions, so their truth is not a coincidence. Even more
weakly, a correlationist may argue that nomic dependence is enough
to avoid coincidence: psychophysical laws connecting processes and
consciousness explain the correctness of our intuitions.
Even for these views, however, it is hard to avoid a sense of coincidence entirely. As long as we have modal independence, so that the
meta-problem processes could have come apart from consciousness, it
can seem lucky that they have not. Where psychophysical laws are
concerned, it seems lucky that the laws are as they are. Only this luck
ensures that we are not in a zombie world with physical processes and
phenomenal intuitions but no consciousness, or in an inverted world
where these processes yield pleasure when we feel pain. Where
realization is concerned, it seems lucky that the meta-problem processes are in fact realized by consciousness rather than by something
else. As before it is not obvious that modal independence is always
objectionable in this way: in the case of tables, the mere possibility
that our table-beliefs could occur without tables need not make the
truth of these beliefs coincidental. And it is arguable that there is
always some luck in beliefs governed by laws of nature. Nevertheless,
in the case of consciousness one has a very strong sort of modal
independence, in that there seems to be a near-complete structural
explanation of the intuitions that could obtain without consciousness.
It is easy to get the sense that what really explains the intuitions is the
structure of cognitive processes, and the fact that consciousness is
connected to that structure is something of a fortunate and optional
extra. More needs to be said to remove any sense of fortunate
coincidence.33
One way to go further is to develop a view where only consciousness could realize the relevant meta-problem processes, perhaps given
certain constraints. For example, on the ‘phenomenal powers’ view
put forward by Mørch (2018), phenomenal states are causal powers as
part of their nature. On a strong version of this view, certain causal
powers are essentially phenomenal powers, and the relevant causal
 33 For coincidence arguments based on modal independence, see Latham (1998) and
Yudkowsky (2008). See also Shaffer (1964) for a coincidence argument against
parallelism.
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THE META-PROBLEM OF CONSCIOUSNESS 49
roles could not be played without consciousness. On a view like this,
it need not be a coincidence that the relevant judgments are brought
about by consciousness.
All this brings out the strong pressure for any non-illusionist view of
consciousness to integrate consciousness and meta-problem processes
as closely as we can. I think the most promising view for reductionists
and non-reductionists alike is realizationism. The research project for
the realizationist is to spell out a satisfactory version of the view
showing how consciousness realizes meta-problem processes in a way
that removes the worries about debunking and about coincidence.
6. What Sort of Illusionism?
Strong illusionists deny that consciousness exists. Weak illusionists
allow that consciousness exists, but say that it does not have certain
crucial properties that it seems to have. For example, weak illusionists
may hold that consciousness seems to be intrinsic, or non-physical, or
non-representational, or primitive, or ineffable, or non-functional, but
it is not.
In practice, there are more weak illusionists than strong illusionism,
since strong illusionism is widely regarded as very implausible. A
number of illusionists (e.g. Graziano, 2016; Humphrey, 2016; forthcoming) have explicitly rejected strong illusionism in favour of some
sort of weak illusionism in recent years.
Still, Frankish (2012; 2016) has argued that illusionists who want to
use illusionism to dissolve the hard problem of consciousness should
be strong illusionists. I think he is correct about this, although my
reasons are somewhat different. The basic reason, as I see it, is that the
hard problem does not turn on the claim that consciousness is
intrinsic, or non-physical, or non-representational, or primitive, and so
on. For example, we can be agnostic about whether consciousness is
intrinsic, or hold that it is extrinsic, and the hard problem arises as
strongly as ever: why is it that when certain brain processes occur,
there is something it is like to be us? The same goes for nonphysicality, non-representationality, primitiveness, ineffability, and so
on. Of course if the appearance that consciousness is non-physical is
an illusion, then consciousness is physical, and the letter of materialism is saved. But this does little to address the hard problem: we still
have no explanation of why there is something it is like to be us.
To generate the hard problem of consciousness, all we need is the
basic fact that there is something it is like to be us. We do not need
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further claims about intrinsicness, non-physicality, and so on. So if an
illusionist wants to reject this route to the hard problem, they need to
deny that there is anything it is like to be us, or perhaps to hold that
the whole idea of there being something it is like to be us is
incoherent. But to do this is to deny that we are phenomenally conscious, or to hold that the whole idea of phenomenal consciousness is
incoherent. And to do this is to be a strong illusionist. So, to dissolve
the hard problem of consciousness, illusionists need to be strong
illusionists.
There is one sort of weak illusionism that may seem to escape this
critique. This sort of weak illusionism allows that there is phenomenal
consciousness, but only in the sense where phenomenal consciousness
is understood functionally: for example, perhaps phenomenal consciousness might be understood as whatever brings about our reports
about consciousness. The hard problem turns crucially on the claim
that the concept of phenomenal consciousness is not a functional concept: that is, it is not a concept of bringing about certain behaviours
and other cognitive consequences. This is what generates the gap
between explaining behavioural functions and explaining consciousness. If phenomenal consciousness is a functional concept, the gap
disappears.
I think this view is an important one, but it should be understood as
a form of strong illusionism. The reason is that any plausible form of
illusionism should allow that our ordinary concept of phenomenal
consciousness is not a functional concept. Our ordinary concepts of
phenomenal consciousness are phenomenal concepts, which are the
central introspective concepts deployed in the meta-problem processes. The thesis that these concepts are not functional concepts is
crucial to solving the meta-problem. If our ordinary concepts of consciousness were functional concepts, then there would be no hard
problem of consciousness, or at least the problem would be much
easier to dismiss. So any view that says there is phenomenal consciousness only in a sense where this is understood functionally is in
effect a view where our ordinary (non-functionally defined) concept
of phenomenal consciousness does not refer. And that is a form of
strong illusionism.
Something like this analysis can be applied to the three varieties of
illusionism distinguished earlier. The first view, a form of strong
illusionism, identifies consciousness with the primitive properties
represented by meta-problem processes, and denies that they exist.
The latter two views, which are forms of weak illusionism, identify
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consciousness with either lower-order or higher-order meta-problem
processes, allowing that consciousness exists but it is not as it seems
to be.
At one level, the choice between these options is verbal. All three
views can allow that the primitive properties do not exist while
allowing that higher-order and lower-order meta-problem processes
exist. The three views just differ in which of these three they call
‘phenomenal consciousness’.
At the same time, there is a natural constraint on what to call
‘phenomenal consciousness’. As we have seen, phenomenal consciousness is what is picked out by phenomenal concepts, which are
the central introspective concepts involved in meta-problem processes.
These concepts purport to pick out primitive properties, and on the
illusionist view no such primitive properties are instantiated. So it
makes sense for illusionists to be strong illusionists, holding that
phenomenal consciousness is not instantiated.
From this perspective, the version of weak illusionism where consciousness is identified with higher-order meta-problem states is
especially unmotivated. It is extremely implausible that phenomenal
concepts pick out these higher-order states. There is perhaps somewhat more motivation for the alternative version of weak illusionism
where consciousness is identified with lower-order meta-problem
states, such as physical/functional states of perception, attention, or
representation. Some illusionists may hold that although phenomenal
concepts purport to pick out primitive properties, they in fact pick out
lower-order meta-problem states, perhaps on the ground that these
states are what phenomenal concepts are tracking in the actual world.
This lower-order variety of weak illusionism is most naturally seen
as a sort of type-B materialism about consciousness, on which our
concept of phenomenal consciousness is a non-functional concept, so
that there is an epistemic gap between the physical and the
phenomenal, but on which this concept picks out physical/functional
properties, so that there is no ontological gap between the physical and
the phenomenal. I have given extensive arguments against views of
this sort in other work (e.g. Chalmers, 2007), and I will not repeat
them here. Type-B materialism is a familiar philosophical strategy for
dealing with the problem of consciousness, with familiar benefits and
problems.
The really distinctive illusionist approach to the mind–body problem
is instead a version of type-A materialism, on which there is no
epistemic gap. The illusionist should allow that there seems to be an
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epistemic gap — that is, there seem to be phenomenal truths that are
not deducible from physical truths — but that in fact this apparent gap
is an illusion. Given the very plausible claim that our phenomenal
concepts are not functional concepts, so that there are no a priori
connections between physical and phenomenal concepts, it is natural
for the type-A illusionist to cash out their position by saying that there
are no phenomenal truths. Phenomenal consciousness seems to exist,
but it does not exist.
This analysis of specific responses to the meta-problem coheres
with the general analysis above. In so far as illusionism is to be a
distinctive way of dissolving the hard problem, the best form of
illusionism is strong illusionism.
This is not to say that weak illusionism is false. In fact, I think some
version of it is almost certainly true. For example, I think that visual
consciousness initially seems to be fully detailed through the visual
field, but this is an introspective illusion. But weak illusionism of this
sort does not do much to dissolve the hard problem. The same goes for
other forms of weak illusionism that I have discussed above. To make
the hard problem itself into a sort of illusion, strong illusionism is
required.
7. An Argument Against Illusionism
This makes for a simple argument against illusionism, at least as a
strategy for dissolving the hard problem.
1. If illusionism can dissolve the hard problem, strong illusionism
is true.
2. Strong illusionism is false.
____________
3. Illusionism cannot dissolve the hard problem.
I have defended the first premise above, so it remains to defend the
second. Some philosophers think that strong illusionism is incoherent.
They hold that illusions are automatically experiences (phenomenally
conscious states), so that if consciousness is an illusion, the illusion is
itself an experience, so that there is phenomenal consciousness after
all. I do not think strong illusionism is incoherent. The strong illusionist can simply understand illusions non-experientially as judgments,
intuitions, or dispositions to report.
A nice illustration is provided by the ‘grand illusion’ on which
visual consciousness seems to be detailed throughout the visual field
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THE META-PROBLEM OF CONSCIOUSNESS 53
(see e.g. Blackmore, 2002). We have the illusion that we have detailed
conscious experiences all the way through. This illusion need not
correspond to an experience of its own. It is simply a false judgment
that need not be a phenomenally conscious state. We can think of
strong illusionism as simply extending this illusionism about some
apparent conscious experiences to all conscious experiences. We
judge that there are experiences, when in fact there are not. Perhaps
this view is implausible, but it is not incoherent.
Strong illusionism is not incoherent, but I think it is empirically
false. I think the best argument against it is a simple Moorean argument, reminiscent of Moore’s pointing to his hands to demonstrate
that there is an external world.
1. People sometimes feel pain.
2. If strong illusionism is true, no one feels pain.
_______________
3. Strong illusionism is false.
Premise 1 seems obviously true. Premise 2 follows from the dual
claims that feeling pain is a conscious experience, and that illusionism
denies that there are any conscious experiences.
At this point, a non-full-blooded illusionist might say they do not
intend to deny that we feel pain. For example, they might say that we
feel pain in a non-phenomenal way or non-experiential or nonconscious way. But this claim is of dubious coherence. In the ordinary
sense of the word ‘feel’, to feel pain is to experience pain. And when
one feels pain in this sense, there is something it is like to undergo the
pain, almost by definition.
I think a strong illusionist should really deny premise 1 (as Dennett
did in his 1978 paper ‘Why You Can’t Make a Computer that Feels
Pain’). That is, they should deny that people ever feel pain, at least in
any sense that entails that they experience pain. The illusionist can
allow that at best people undergo processes of pain, and register them,
but they do not experience pain, and they do not feel pain.
Of course to deny that people feel pain is to deny something
apparently obvious. But I think it is of the essence of strong illusionism about consciousness to deny something apparently obvious —
something so initially obvious that it seems undeniable. If the strong
illusionist tries to avoid this route, they will not do justice to the
strength of the intuitions that underlie the hard problem. For example,
sophisticated illusionists may suggest that we feel pain in a weak
(functional) sense but not a strong (phenomenal) sense. But crucially,
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54 D.J. CHALMERS
the sense in which it is introspectively obvious that we feel pain is the
phenomenal sense. In particular, it is the sense involving phenomenal
concepts, which are the key concepts in our introspective self-models.
Strong illusionists about consciousness are committed to denying
the central apparently introspectively obvious data about consciousness, and should not try to avoid it. If they do so, they will inevitably
fail to dissolve the hard problem in the same way that weak illusionists failed in the previous section. The moment one acknowledges that
people genuinely feel pain (in the introspectively obvious sense), one
faces the hard problem: why are physical pain processes accompanied
by the feeling of pain? This is as central a version of the hard problem
as any, and it can be posed using the introspectively obvious datum
alone. To dissolve it in the illusionist way, an illusionist should hold
that the feeling of pain is an illusion.
Certainly, if I were a strong illusionist, I would deny that anyone
ever feels pain. I would say that the experience of pain is an introspective illusion. When we seem to be experiencing pain, our brains
are simply registering and negatively evaluating some states of one’s
body, with associated dispositions to change these states where possible. There is no experience of pain, and no feeling of pain. Experiences and feelings are simply states represented by misleading introspective models, and these states do not really exist.
That said, I think illusionism is obviously false, because it is
obvious that people feel pain.
Around this point there is a familiar sort of dialogue:
Realist: People obviously feel pain, so illusionism is false.
Illusionist: You are begging the question against me, since I deny
that people feel pain.
Realist: I am not begging the question. It is antecedently obvious
that people feel pain, and the claim has support that does not
depend on assuming any philosophical conclusions. In fact this
claim is more obvious than any philosophical view, including
those views that motivate illusionism.
Illusionist: I agree that it is obvious that people feel pain, but
obvious claims can be false, and this is one of them. In fact, my
illusionist view predicts that people will find it obvious that they
feel pain, even though they do not.
Realist: I agree that illusionism predicts this. Nevertheless, the
datum here is not that I find it obvious that people feel pain. The
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THE META-PROBLEM OF CONSCIOUSNESS 55
datum is that people feel pain. Your view denies this datum, so it
is false.
Illusionist: My view predicts that you will find my view
unbelievable, so your denial simply confirms my view rather than
opposing it.
Realist: I agree that my denial is not evidence against your view.
The evidence against your view is that people feel pain.
Illusionist: I don’t think that is genuine evidence.
Realist: If you were right, being me would be nothing like this.
But it is something like this.
Illusionist: No. If ‘this’ is how being you seems to be, then in fact
being you is nothing like this. If ‘this’ is how being you actually
is, then being you is just like this, but it is unlike how being you
seems to be.
And the dialogue goes on. Dialectically, the illusionist side is much
more interesting than the realist side. Looking at the dialectic
abstractly, it is easy to sympathize with the illusionist’s debunking
against the realist’s foot-stamping. Still, reflecting on all the data, I
think that the realist’s side is the right one.
8. Conclusion
The meta-problem of consciousness is interesting not least because it
is hard to avoid taking a position that others regard as crazy.
Here is Galen Strawson (2017) on strong illusionism, in a lecture
entitled ‘One Hundred Years of Consciousness (A Long Training in
Absurdity)’:
There occurred in the twentieth century the most remarkable episode in
the whole history of ideas — the whole history of human thought. A
number of thinkers denied the existence of something we know with
certainty to exist: consciousness, conscious experience.
Here is Eliezer Yudkowsky (2008) on non-reductionist realism about
consciousness in light of the meta-problem (focusing especially on
epiphenomenal property dualism):
Based on my limited experience, the Zombie Argument may be a candidate for the most deranged idea in all of philosophy… I do not see any
way to evade the charge that, on Chalmers’s own theory, this separable
outer Chalmers is deranged. This is the part of Chalmers that is the
same in this world, or the Zombie World; and in either world it writes
philosophy papers on consciousness for no valid reason. Chalmers’s
philosophy papers are not output by that inner core of awareness and
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56 D.J. CHALMERS
belief-in-awareness, they are output by the mere physics of the internal
narrative that makes Chalmers’s fingers strike the keys of his computer.
And yet this deranged outer Chalmers is writing philosophy papers that
just happen to be perfectly right, by a separate and additional miracle.
Of course there is middle ground between denying consciousness and
saying that consciousness is epiphenomenal, but the middle ground
tends to lead back to Scylla or Charybdis. On the deflationary side,
there are certainly forms of weak illusionism, but these do not help
much with the hard problem. Versions that help with the hard problem
need to deny the obvious, which is precisely what makes them seem
absurd. On the realist side, there are non-epiphenomenalist forms of
realism about consciousness, but most of these can be subjected to a
weaker form of the same critique: once we can explain our conviction
that consciousness exists without assuming that consciousness exists,
the fact that the conviction is true seems somewhat miraculous.
I think that, as things stand, neither illusionism nor realism has a
truly satisfactory response to the charge of absurdity. Perhaps such a
response can be found, but it will require major new ideas.
For the illusionist, what is needed is an explanation of how having a
mind without phenomenal consciousness could be like this, even
though it is not at all the way that it seems. What would be ideal is
something that does more than explaining our reactions and judgments
(which seems to simply miss the phenomenon), without going so far
as explaining the conscious experience itself (which an illusionist
cannot do).
For the realist, what is needed is an explanation that shows how
consciousness and meta-problem processes are inextricably intertwined. What would be ideal is an explanation of why the metaproblem processes are by their nature grounded in consciousness, even
if it is metaphysically possible for them to occur without
consciousness.
We do not have these explanations yet. If they can be developed,
they might push us toward a satisfactory solution to the hard problem
of consciousness. In the meantime, the meta-problem is a potentially
tractable research project for everyone.
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The phenomenal judgment approach, Journal of Mind and Behavior, 35,pp. 51–
70.
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THE META-PROBLEM OF CONSCIOUSNESS 57
Armstrong, D.M. (1968a) The headless woman illusion and the defence of
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Blackmore, S.J. (2002) The grand illusion: Why consciousness exists only when
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