# What are the actual arguments in favor of computationalism as a theory of identity?

A few months ago, Rob Bensinger made [a rather long post](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me) (that even [got curated](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=5FvzQTGFFaEEKgYuG)) in which he expressed his views on several questions related to [personal identity](https://www.lesswrong.com/tag/personal-identity) and [anticipated experiences](https://www.lesswrong.com/tag/anticipated-experiences) in the context of potential [uploading and emulation](https://www.lesswrong.com/tag/whole-brain-emulation). A critical implicit assumption behind the exposition and reasoning he offered was the adoption of what I have [described](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#5DqgcLuuTobiKqZAe) as the "standard LW-computationalist frame." In response to me highlighting this, Ruben Bloom [said](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#rMEyB5b4ZkiLz6Aqu) the following:

> I differ from Rob in that I do think his piece should have flagged the assumption of ~computationalism, but think the assumption is reasonable enough to not have argued for in this piece.  
>   
> I do think it is interesting philosophical discussion to hash it out, for the sake of rigor and really pushing for clarity. I'm sad that I don't think I could dive in deep on the topic right now.

However, as I [pointed out](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#rXnoqL2hs9qXmJvET) in that thread, the lack of argumentation or discussion of *this particular assumption* throughout the history of the site means it's highly questionable to say that assuming it is "reasonable enough":

> [As TAG has written](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#7sdbeic47ghFfCBD9) a number of times, the computationalist thesis seems not to have been convincingly (or even concretely) argued for in *any* LessWrong post or sequence (including Eliezer's Sequences).

TAG himself [made](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=7sdbeic47ghFfCBD9) a similar and important point in a different comment on the same post:

> Naturalism and reductionism are not sufficient to rigourously prove either form of computationalism -- that performing a certain class of computations is sufficient to be conscious in general, or that performing a specific one is sufficient to be a particular conscious individual.
> 
> This has been going on for years: most rationalists believe in computationalism, none have a really good reason to.
> 
> Arguing down Cartesian dualism (the thing rationalists always do) doesn't increase the probability of computationalism, because there are further possibilities , including physicalism-without-computationalism (the one rationalists keep overlooking) , and scepticism about consciousness/identity.
> 
> One can of course adopt a belief in computationalism, or something else, in the basis of intuitions or probabilities. But then one is very much in the ream of Modest Epistemology, and needs to behave accordingly.
> 
> "My issue is not with your conclusion, it’s precisely with your absolute certainty, which imo you support with cyclical argumentation based on weak premises".

And, indeed (ironically enough), in response to [andesoldes's excellent distillation](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#opJbYudzcBDDAHGNp) of Rob's position and subsequent [detailed and concrete explanation](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=EMrfbXx48iyqrQjiv) of why it seems wrong to have this degree of confidence in his beliefs, Bensinger *yet again* [replied](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#cmN9N2vKaseyLmLoj) in a manner that seemed to indicate he thought he was arguing against a dualist who thought there was a little [ghost inside the machine](https://www.lesswrong.com/posts/cnYHFNBF3kZEyx24v/ghosts-in-the-machine), an invisible [homunculus](https://www.lesswrong.com/tag/homunculus-fallacy) that violated [physicalism](https://www.greaterwrong.com/s/FqgKAHZAiZn9JAjDo):

> I agree that "I made a non-destructive software copy of myself and then experienced the future of my physical self rather than the future of my digital copy" is nonzero Bayesian evidence that physical brains have a Cartesian Soul that is responsible for the brain's phenomenal consciousness; the Cartesian Soul hypothesis does predict that data. But the prior probability of Cartesian Souls is low enough that I don't think it should matter.
> 
> You need some prior reason to believe in this Soul in the first place; the same as if you flipped a coin, it came up heads, and you said "aha, this is perfectly predicted by the existence of an invisible leprechaun who wanted that coin to come up heads!". Losing a coinflip isn't a surprising enough outcome to overcome the prior against invisible leprechauns.

But, as andesoldes later [ably pointed out](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=EMrfbXx48iyqrQjiv):

> You're missing the bigger picture and pattern-matching in the wrong direction. I am not saying the above because I have a need to preserve my "soul" due to misguided intuitions. On the contrary, the reason for my disagreement is that I believe **you are not staring into the abyss of physicalism hard enough**. When I said I'm agnostic in my previous comment, I said it because physics and empiricism lead me to consider reality as more "unfamiliar"  than you do (assuming that my model of your beliefs is accurate). From my perspective, your post and your conclusions are written with an unwarranted degree of certainty, because imo your conception of physics and physicalism is too limited. Your post makes it seem like your conclusions are obvious because "physics" makes them the only option, but they are actually a product of implicit and unacknowledged philosophical assumptions, which (imo) you inherited from intuitions based on classical physics.

More specifically, as I [wrote](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=5DqgcLuuTobiKqZAe) in response to Seth Herd, "\[the\] standard LW-computationalist frame reads to me as substantively anti-physicalist and mostly unreasonable to believe in" for reasons I gave in [my explanation](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=rXnoqL2hs9qXmJvET) to Bloom:

> What has been argued for, over and over again, is physicalism, and then more and more rejections of dualist conceptions of souls. 
> 
> That's perfectly fine, but "souls don't exist and thus consciousness and identity must function on top of a physical substrate" is very different from "the identity of a being is given by the *abstract classical computation performed by a particular (and reified) subset of the brain's electronic circuit,*" and the latter has *never* been given compelling explanations or evidence. [^getqaipl14h] This is despite the fact that the particular conclusions that have become part of the ethos of LW about stuff like brain emulation, cryonics etc are necessarily reliant on the latter, not the former. 
> 
> As a general matter, accepting physicalism as correct would naturally lead one to the conclusion that what runs on top of the physical substrate works on the basis of... *what is physically there* (which, to the best of our current understanding, can be represented through [Quantum Mechanical probability amplitudes](https://www.lesswrong.com/posts/RLScTpwc5W2gGGrL9/identity-isn-t-in-specific-atoms)), not what conclusions you draw from a mathematical model that abstracts away quantum randomness in favor of a classical picture, the entire brain structure in favor of (a slightly augmented version of) its connectome, and the entire chemical make-up of it in favor of its electrical connections. As I have mentioned, that is a mere *model* that represents a *very lossy* compression of what is going on; it is [not the same](https://www.lesswrong.com/posts/KJ9MFBPwXGwNpadf2/skill-the-map-is-not-the-territory) as the real thing, and conflating the two is an error that has been going on here for far too long. Of course, it very well [might be the case](https://www.lesswrong.com/posts/QGkYCwyC7wTDyt3yT/0-and-1-are-not-probabilities) that Rob and the computationalists are right about these issues, but the explanation up to now should make it clear why it is on them to provide evidence for their conclusion.

The accuracy of this interpretation of the LW-computationalist view seems to have been confirmed by its proponents, *implicitly* by Bensinger [continuing](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=Ee8zfuMrYxSDvcacN) the conversation with andesoldes without mentioning any disagreement when the latter [explicitly asked him](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=ZwSscp3MSdb5KLrqx) "First off, would you agree with my model of your beliefs? Would you consider it an accurate description?" and by cousin_it [saying](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=J3wso45WeEiokhebR) that "uploading \[going\] according to plan" means "the map of your neurons and connections has been copied into a computer", and *explicitly* by Seth Herd [claiming](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=yEpzyKbWQGdnRre8x) that "your mind is a pattern instantiated in matter" and by Bloom, who [wrote](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=rMEyB5b4ZkiLz6Aqu) the following:

> To answer your question in your other comment. I reckon with some time I could write an explainer for why **we should very reasonable assume consciousness is the result of local brain stuff and nothing else (and also not quantum stuff)**, though I'd be surprised if I could easily write something so rigorous that you'd find it fully satisfactory.

(Emphasis mine.) 

When Seth Herd [restated](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#TnvGZFjsrso2srfrx) computationalist conclusions, once again without much argumentation ("Noncomputational physicalism sounds like it's just confused. Physics performs computations and can't be separated from doing that. Dual aspect theory is incoherent because you can't have our physics without doing computation that can create a being that claims and experiences consciousness like we do"), I summarized a relevant part of my skepticism as follows:

> As I read these statements, they fail to contend with a rather basic [map-territory distinction](https://www.lesswrong.com/posts/KJ9MFBPwXGwNpadf2/skill-the-map-is-not-the-territory) that lies at the core of "physics" and "computation." 
> 
> The basic concept of *computation* at issue here is a feature of the *map* you could use to approximate reality (i.e., the territory) . It is merely part of a mathematical *model* that, as I've described in response to Ruby earlier, [represents a very lossy compression](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me#rXnoqL2hs9qXmJvET) of the underlying physical substrate [^z2x0l2pf96o]. This is because, in this restricted and epistemically hobbled ontology, what is given inordinate attention is the *abstract classical computation performed by a particular subset of the brain's electronic circuit*. This is what makes it anti-physicalist, as I have explained:
> 
> \[...\]
> 
> So when you talk about a "pattern instantiated by physics as a pure result of how physics works", you're not pointing to anything meaningful in the territory, rather only something that makes sense in the particular ontology you have chosen to use to view it through, a frame that [I have explained my skepticism of already](https://www.lesswrong.com/posts/zPM5r3RjossttDrpw/when-is-a-mind-me?commentId=5DqgcLuuTobiKqZAe).

So, to finish up the exposition and background behind this question, what are the *actual* arguments in favor of the computationalist thesis? If you agree with the latter philosophy,[^fp79wcsbhus] why do you not think it to be the case that computationalism is anti-physicalist by failing a basic map-territory distinction due to how it reifies ideas like "computation" as being parts of the territory as opposed to mere artifacts of a mathematical model that attempts, imperfectly and lossily, to approximate reality?

[^fp79wcsbhus]: In my current model of this situation, I have some strong suspicions about the reasons why LW converged on this worldview despite the complete lack of solid argumentation in its favor, but I prefer to withhold the psychoanalysis and pathologizing of my interlocutors (at least until after the object-level matters are resolved satisfactorily).