identity theory

The Identity Theory : Mental states are physical states of the brain. Something is in pain only if, and because, its c-fibers are firing.

The Modal Argument 1)If the Identity Theory is correct, then pain is identical to the firing of C-fibers. 2)If pain is identical to the firing of C-fibers, then pain is necessarily identical to the firing of C-fibers. 3)If pain is necessarily identical to firing of C- fibers, then pain could not have existed without the firing of C-fibers. 4)Pain could have existed without the firing of C-fibers. 5)The Identity Theory is incorrect.

The Parody Argument 1)If current chemical theory is correct, then water is identical to H2O. 2)If water is identical to H2O, then water is necessarily identical to H2O. 3)If water is necessarily identical to H2O, then water could not have existed without H2O. 4)Water could have existed without H2O. 5)Current chemical theory is not correct.

When someone says, inaccurately, that heat might have turned out not to be molecular motion, what is true in what he says is that someone could have sensed a phenomenon in the same way we sense heat… even though that phenomenon was not molecular motion. He means, additionally, that the planet might have been inhabited by creatures who [got the sensation we got from heat]… in the presence of something else… even though it would not be molecular motion (and therefore not heat!), which was causing the sensation. -Saul Kripke, Naming and Necessity

When someone says, inaccurately, that water might have turned out not to be H2O, what is true in what he says is that someone could have interacted with a substance in the same way we interact with water… even though that substance was not H2O. He means, additionally, that the planet might have been inhabited by creatures who got the sensations we get from water—the taste, the feel, etc.– in the presence of something else… even though it would not be H2O (and therefore not water!), which was causing the sensations.

The Parody Argument 1)If current chemical theory is correct, then water is identical to H2O. 2)If water is identical to H2O, then water is necessarily identical to H2O. 3)If water is necessarily identical to H2O, then water could not have existed without H2O. 4)Water could have existed without H2O. 5)Current chemical theory is not correct.

When someone says, inaccurately, that pain might have turned out not to be C-fibers firing, what is true in what he says is that someone could have sensed a phenomenon in the same way we sense pain… even though that phenomenon was not C-fibers firing. He means, additionally, that the planet might have been inhabited by creatures who [got the sensation we got from pain]… in the presence of something else… even though it would not be C-fibers firing (and therefore not pain!), which was causing the sensation.

The Modal Argument 1)If the Identity Theory is correct, then pain is identical to the firing of C-fibers. 2)If pain is identical to the firing of C-fibers, then pain is necessarily identical to the firing of C-fibers. 3)If pain is necessarily identical to firing of C- fibers, then pain could not have existed without the firing of C-fibers. 4)Pain could have existed without the firing of C-fibers. 5)The Identity Theory is inorrect.

The Identity Theory : Mental states are physical states of the brain. Something is in pain only if, and because, its c-fibers are firing. The Relativized Identity Theory : Mental states are physical states of the brain. (Something is in human-pain only if, and because, its c-fibers are firing) and (something is in squid-pain only if, and because, its d-fibers are firing) and…

The Identity Theory : Mental states are physical states of the brain. Something is in pain only if, and because, its c-fibers are firing. The Disjunctive Identity Theory : Mental states are physical states of the brain. Something is in pain only if, and because (it’s a human and its c-fibers are firing) or (it’s a squid and its d-fibers are firing) or...

In the previous chapter we noticed that mental states can be multiply realized. In humans the state which realizes pain is (say) c-fiber firing; in squid it’s (say) d- fiber firing. Multiple realization raises a puzzle: what do old Eight-legs and I have in common when we are both in pain? It can’t be c-fiber firing because Eight-legs has no c-fibers (or so I will assume). And it can’t be d-fiber firing because I have no d-fibers (or so I will assume). In virtue of what, then, is it true that Eight-legs and I are both in pain? Functionalism provides an answer to this puzzle. Ravenscroft, Philosophy of Mind