## Philosophical foundations of neuroscience.

The problem at issue here is the nature of connection between the
features of the experiments described in psychological/mentalistic terms
and the features described in spacio-temporally-based physical terms.
This question is an aspect of the long-standing problem of the
relationship between mind and matter, which has a history dating back to
the time of the ancient Greeks. The issue was rekindled by the rise of
Newtonian physics during the seventeenth century, and it generated a
huge body of speculation and argumentation during the second half of the
twentieth century.

It is neither appropriate nor feasible try to review or explain here the
complexities of contemporary philosophical opinions on this question,
except to say that the reigning view is "materialism," and that: (1),
there is no agreement among its proponents as to how to make rational
good sense of this doctrine (Horgan, 1994); and (2), the doctrine, and
its supporters, seem, nevertheless, to have strongly influenced the
thinking of many neuroscientists.

The central thesis of materialism is that:

"The human body is a causally complete physico-chemical system: although
the body is highly susceptible to external causal influences, all
physical events in the body, and all bodily movements are fully
explainable in physico-chemical terms." (Horgan, 1994:472)

This thesis is, from a contemporary physics point of view, very obscure:
What does "causally complete physico-chemical system" mean? It seems to
be referring back to the seventheenth/nineteenth century
classical-physics conception of nature, which is now known to
fundamentally false. If the doctrine does indeed assume a
classical-physics-type of conception of nature, then every bodily
movement would indeed be in principle fully explainable in
physico-chemical terms. But no reference to mental states or events
occurs in classical physics. Hence one is faced with a question that the
proponents of materialism have debated at length: how does one inject
causally efficacious mind into this causally complete physical
description of nature that make no mention of mind.

The ingenuity of philosophers has provided many possible answers, but
every proposal seems flawed to other philosophers, and debate continues.

In addition to the problem of trying to attach causally efficacious mind
onto a causally complete mindless theory, there is a still more basic
problem: classical physical theory is known to be fundamentally false,
and in principle inapplicable to systems, such as brains, that depend
sensitively upon, for example, the motions of ions. And there is also
the problem that the physico-classical aspect of contemporary physical
theory, by itself, does not yield any predictions about empirically
accessible data. To obtain even statistical predictions in quantum
theory one needs to bring in "The Observer," who is described,
fundamentally, in psychological/mentalistic terms. And this "Observer"
plays a *participatory role* in the quantum formulation: he is not the
purely passive observer of classical physics. He enters into the
dynamics in a causally efficacious way.

In view of these profound, and apparently profoundly relevant,
deviations of contemporary physics from what is essentially the
seventeenth century materialist creation of Isaac Newton, it is strange
that twenty-first century neuroscientists should adhere so unwaveringly
to that seemingly inappropriate and ill-defined doctrine based on a
now-known-to-be-fundamentally-false physical theory.

What orthodox quantum theory affirms, and materialism appears to deny,
is that psychologically described realities enter *fundamentally* into
the scientific description of phenomena, and have, *per se*, causal
effects that are *not explained* solely in terms of the physical laws
that are the generalization of the physical laws of classical physical
theory. These causal effects are, however, explained by using other laws
of quantum physics, which have no analog in classical physics.

The big problem with materialism as a basis for neuroscience is that it
elevates to primary status, by fiat, the (actually nonexistent) physical
entities of classical physics, and relegates to secondary status the
experiential realities that are the primary variables of pragmatic
empirical science. Classical physics does not explain how functional
properties come to be connected to experiential realities, and hence
fails to explain the causal efficacy of our thoughts. The power of our
thought to influence bodily action seems, therefore, from the standpoint
of classical physics, to be some sort of illusion, or at least
unexplained mystery. Quantum theory, on the other hand, displays the
mechanism of conscious control, and hence dispels the mystery. The
details are given in a later section.

\[Horgan, Terence E. (1994). Physicalism. In Samuel Guttenplan (Ed.) *A
companion to the philosophy of mind* (471-479). Oxford: Blackwell.\]