Modal Illusions and Impossible Zombie Worlds
Abstract
This thesis concerns three topics: the conceivability argument (CA) against physicalism, the Kripkean necessary a posteriori, and the two-dimensional semantic framework. In Chapter 1, I lay out the debate between a posteriori physicalists and two-dimensionalist CA apologists. In Chapter 2, I argue that the Kripkean necessary a posteriori is a philosophical achievement both in its own right and in securing a posteriori physicalism against CA, but it is also susceptible to several objections; those objections have largely enlightened the enterprise of two-dimensionalism. In Chapter 3, I elaborate how two-dimensionalism purports to disarm the necessary a posteriori and how it purports to help strengthen CA; I then identify what I take to be the Achilles heel of two-dimensionalism, and that is the semantic characterisation of the so-called primary intension. In Chapter 4, I argue that two-dimensionalism is untenable, because it arises from the exploitation of some correctable metalinguistic inadequacies of Kripke’s own account of the necessary a posteriori. Once the two-dimensionalist metalinguistic misreading of the necessary a posteriori is corrected by Kripke’s alternative essentialist account, two-dimensionalism will collapse, and the two-dimensional conceivability argument will fail to challenge physicalism.