What is it like to be a bat?

Can we just all admit there has basically been no real progress made to the mind-body problem. They all rest on metaphysical axioms of which no one has any proof of. Physicalism is about as plausible as solipsism.

Exhibit a

> Nagel begins by assuming that "conscious experience is a widespread phenomenon" present in many animals (particularly mammals), even though it is "difficult to say [...] what provides evidence of it".

> Physicalism is about as plausible as solipsism.

Physicalism is an ontological assertion that is almost certainly true, and is adhered to by nearly all scientists and most philosophers of mind. Solipsism is an ontological assertion that could only possibly be true for one person, and is generally dismissed. They are at opposite ends of the plausibility scale.

One big problem with physicalism is that many alleged arguments in its favor are nothing of the sort. Any argument for physicalism that refers to neurological observation is invalid. Physicalism claims that all mental events can be reduced to physical events. But you cannot look at physical events to prove this. No matter the detail in which you describe a physical event, you can't use this to prove, or even argue in favor of, the thesis that all mental events can be reduced to the physical.

It's like describing the inside of a house in very great detail, and then using this to argue that there's nothing outside the house. The method is explicitly limiting its scope to the inside of the house, so can say nothing about what's outside, for or against. Same with physicalism: most arguments in its favor limit their method to looking at the physical, so in practice say nothing about whether this is all there is.

You're making a number of unsupported assertions. There's a massive amount of literature in support of physicalism. And it's a far cry from "there's no proof of x" to "x is invalid". No metaphysical stance can be proved.

> Same with physicalism: most arguments in its favor limit their method to looking at the physical, so in practice say nothing about whether this is all there is.

This is simply wrong ... there are very strong arguments that, when we're looking at mental events, we are looking at the physical. To say that arguments for physicalism are limited to looking at the physical is a circular argument that presupposes that physicalism is wrong. The arguments for physicalism absolutely are not based at looking at a limited set of things, they are logical arguments that there's no way to escape being physical ... certainly Descartes' dualism is long dead due to the interaction problem -- mental states must be physical in order to be acted upon or act upon the physical. The alternatives are ad hoc nonsense like Chalmers' "bridging laws" that posit that there's a mental world that is kept in tight sync with the physical world by these "bridging laws" that have no description or explanation or reason to believe exist.

> And it's a far cry from "there's no proof of x" to "x is invalid".

Oh this is undoubtedly true, and my argument was limited to the statement that the most common argument for physicalism is invalid. I was not launching an attack on physicalism itself.

> No metaphysical stance can be proved.

That's an interesting metaphysical stance, but again, I'm not trying to prove any metaphysics, just pointing out the main weakness that I see in the physicalist argument. I'm pointing out that any pro-physicalist argument that is a variant of "neuroscience says X" is invalid for the reason I gave: by limiting your scope to S, you can say nothing about anything outside S. This is true regardless of whether there is actually anything outside S, so there is no assumption in my argument that physicalism is wrong.

One argument against physicalism is that if thought or knowledge can be reduced to particles bouncing around, then there is no thought or knowledge. My knowledge that 2+2=4 is about something other than, or different from, the particles in my brain. Knowledge is about the content of the mind, which is different from the associated physical state of the brain. If content is neurons, then content as something my mind considers doesn't exist. If my thought "2+2=4" just is a bunch of particles in my brain doing stuff, then my belief that my thought is true is not even wrong, as the saying goes: just absurd.

I'm no Cartesian dualist though -- the interaction problem is just one problem with his dualism. I think Aristotle and Aquinas basically got the picture of reality right, and their metaphysics can shed yuuuuge amounts of light on the mind-body problem but obviously that's a grossly unfashionable worldview these days :-)

> I'm not trying to prove any metaphysics

You attacked physicalism for not being proven.

I disagree with your arguments and I think they are hopelessly confused. Since our views are conceptually incommensurate, there's no point in continuing.

I'm afraid the physicalist position is absolutely impossible. When I think about something, I'm thinking about something different from the brain state that represents it. There is nothing difficult or subtle about this: if I think about a tiger, I am not thinking about a brain state that is associated therewith.

The physicalist position wants to reduce the mental to the physical. My thought cannot be reduced from the mental to the physical, because my thought is about a tiger, and a tiger cannot be reduced to a brain state.

If physicalism is true, I can't really be thinking about a tiger, because the tiger in my thought has no physical existence-as-a-tiger, and therefore can't have any existence-as-a-tiger at all. But then I'm not really thinking about a tiger. And the same applies to all our thoughts: physicalism would imply that all our thoughts are delusional, and not about reality at all. A non-physicalist view allows my thought to be actually about a tiger, without that tiger-thought having physical existence.

(Note that I have no problem with the view that the mental and the physical co-incide, or have some kind of causal relationship -- this is obviously true -- only with the view that the mental is reducible to the physical.)