Conceivability Arguments and Qualitative Inaccuracy

Abstract

Chapter 3 develops a response to David Chalmers’s conceivability argument against (ordinary) physicalism analogous to the objection to the knowledge argument set out in Chapter 1. The conceivability argument hinges on the claim that it is conceivable, in an appropriately sophisticated way, that a world that is (nothing but) an exact physical duplicate of the actual world feature no phenomenal consciousness – i.e., that a zombie world is conceivable. From this premise the argument reasons to the conclusion that the complete physical truth does not necessitate the complete phenomenal truth, or even any phenomenal truth, and that therefore physicalism is false. I develop a response to this argument appeals to the same central claim as the foregoing reply to the knowledge argument. Physicalism requires that phenomenal truths be a priori derivable from the complete physical truth about the actual world. However, if introspection did represent phenomenal states inaccurately, on analogy with our ordinary visual color representations on Locke’s conception, then the truth of physicalism would not require propositions about phenomenal properties as they are represented introspectively to be derivable a priori from the complete physical truth about the actual world. For if the qualitative natures these phenomenal properties are introspectively represented as having are incorrectly attributed to them, and are features these properties actually lack, then it might well be that all facts about the real natures of phenomenal states are derivable a priori from the complete physical truth after all.