|Twin earth: is an expression from a thought experiment by H. Putnam (H. Putnam, The meaning of ‘meaning’, In Philosophical Papers, Vol. 2 Mind, Language and Reality, Cambridge, 1985). It is assumed that there is a second earth, which resembles our own in every detail, except for the composition of the substance water. However, the twin earth-water has phenomenologically the same properties as our water and is also called water there. The example should show that we cannot determine the reference of expressions independently of the environment. See also reference, externalism, internalism, anti-individualism._____________Annotation: The above characterizations of concepts are neither definitions nor exhausting presentations of problems related to them. Instead, they are intended to give a short introduction to the contributions below. – Lexicon of Arguments. |
Twin Earth/SchifferVsFolk Psychology: must be false because in twin earth, a different belief has the same functional role. - E.g. Ralph believes there are cats. - Twin Earth Ralph believes "there are cats" (but there are twin earth cats).
So twin earth Ralph does not believe that there are cats, so there are two different beliefs but the same functional role.
Twin Earth Ralph is in the same neural Z-type N.
The specification of belief might require reference to cats, but the counterfactual nature of the condition would ensure that N is satisfied for twin earth Ralph. - N.B.: that does not follow from a truth about functional roles in general, but with respect to the theory T* (folk psychology).
Outside the folk psychology: E.g. "every token of "cat" is triggered by viewing a cat".
Incorrect solution: platitude: "typically triggered by cats". This cannot be a necessary condition. - In addition, there are twin earth-examples, where typical belief is unreliable for their own truth. - VsDescription: no solution: "That thing in front of me"._____________Explanation of symbols: Roman numerals indicate the source, arabic numerals indicate the page number. The corresponding books are indicated on the right hand side. ((s)…): Comment by the sender of the contribution.
Remnants of Meaning Cambridge 1987