Abstract: Oscar, living on Earth, believes that his neighbour Amy owns a cat. TwOscar, living on Twin Earth, believes that his neighbour TwAmy owns a cat. Oscar and TwOscar are in qualitatively indistinguishable epistemic situations, but the facts on Earth and Twin Earth are subtly different: Amy owns a cat, but TwAmy does not.
Philosophers have assumed that in such a scenario, Oscar's belief is true, while TwOscar's is false. They have drawn the conclusion that the content of Oscar's belief is different from the content of TwOscar's. And from that, in turn, they've concluded that mental content does not supervene on the internal state of the agent. However, fans of the idea that mental content supervenes on the internal state of the agent have a little-explored alternative option. They might deny that the contents of Oscar and TwOscar's beliefs are straightforwardly truth-conditional. Further, and more drastically, they might deny that our ordinary thoughts are about everyday physical objects, in the sense in which we take Oscar's thought to be straightforwardly about his neighbour Amy.
In this talk, I'll pursue this option, and argue for its viability. After fleshing out the proposal a bit, I'll show that it solves several vexing philosophical problems, such as Frege's Puzzle and the problem of thought about non-existent objects. These motivations supplement well-known arguments for the supervenience of mental content on the agent's internal state.
I'll also defend the proposal against objections. In particular, I'll seek to mitigate the extremeness of the view that mental contents are not truth-conditional, by explaining why, on my proposal, beliefs can still be called true or false in a derivative sense. I'll further argue that this derivative sense is enough to explain the important datum that true beliefs are systematically more useful than false ones.
See the DPhil Seminar website for details.
DPhil Seminar Convenor: Oscar Monroy Perez
