The Cogito and the Metaphysics of Mind

Descartes used the cogito to make two points the epistemological point that introspection affords us absolute certainty of our existence, and the metaphysical point that subjects are thinking things logically distinct from bodies. Most philosophers accept Descartes’s epistemological claim but reject his metaphysical claim. I argue that we cannot do this if the cogito works, then subjects are non-physical. Although I refrain from endorsing an argument for dualism based on this conditional, I discuss how such an argument would differ from the conceivability arguments pursued by Descartes in the Sixth Meditation and by contemporary philosophers. Unlike those arguments, this argument would not be refuted by the discovery of a posteriori identities between physical and phenomenological properties. In other words, it is possible to argue for substance dualism even if phenomenal properties are physical properties.     

Conceivability and possibility

We often decide whether a state of affairs is possible (impossible) by trying to mentally depict a scenario (using words, images, etc.) where the state in question obtains (or fails to obtain). These mental acts (broadly thought of as ‘conceiving’) seem to provide us with an epistemic route to the space of possibilities. The problem this raises is whether conceivability judgments provide justification-conferring grounds for the ensuing possibility-claims (call this the ‘conceivability thesis’). Although the question has a long history, contemporary interest in it was, to a large extent, prompted by Kripke's utilization of modal intuitions in the course of propounding certain influential theses in the philosophy of language and mind. The interest has been given a further boost by the recent two-dimensional approach to the Kripkean framework. In this paper, I begin by providing a detailed examination of a most recent attempt (due to Chalmers) to defend the thesis and argue that it is unsuccessful. This is followed by presenting my own gloss on Kripke's explanation of the illusions of contingency and I close by raising a general problem intended to undermine the prospects for a successful defense of the thesis.     

Conceivability and Epistemic Possibility

The notion of conceivability has traditionally been regarded as crucial to an account of modal knowledge. Despite its importance to modal epistemology, there is no received explication of conceivability. In recent discussions, some have attempted to explicate the notion in terms of epistemic possibility. There are, however, two notions of epistemic possibility, a more familiar one and a novel one. I argue that these two notions are independent of one another. Both are irrelevant to an account of modal knowledge on the predominant view of modal reality. Only the novel notion is relevant and apt on the competing view of modal reality; but this latter view is problematic in light of compelling counterexamples. Insufficient care regarding the independent notions of epistemic possibility can lead to two problems: a gross problem of conflation and a more subtle problem of obscuring a crucial fact of modal epistemology. Either problem needlessly hampers efforts to develop an adequate account of modal knowledge. I conclude that the familiar notion of epistemic possibility (and the very term ‘epistemic possibility’) should be eschewed in the context of modal epistemology.

Predication and Hume's Conceivability Principle

In this paper, I will make the case that an associative account of predication in Hume seems to allow for impossible predicative conceptions—that is, the conceiving of impossible states of affairs involving subjects instantiating properties or qualities—which violate his Conceivability Principle. The natural response is to argue that such conceptions are not clear and distinct, but substantive worries are raised about a number of attempted solutions along these lines. This poses a predicament for Hume scholars: either we must modify or abandon the Conceivability Principle, or reject an associative account of predication, or concede that Hume faces a difficulty he cannot solve.     

Conceivability and Defeasible Modal Justification

This paper advances the thesis that we can justifiably believe philosophically interesting possibility statements. The first part of the paper critically discusses van Inwagens skeptical arguments while at the same time laying some of the foundation for a positive view. The second part of the paper advances a view of conceivability in terms of imaginability, where imaginging can be propositional, pictorial, or a combination of the two, and argues that conceivability can, and often does, provide us with justified beliefs of what is metaphysically possible. The notion of scenarios is developed, as is an account of how filling out scenarios can uncover a defeater or, in many cases, strengthen the justification for the relevant possibility statement.     

Conceivability, rigidity and counterpossibles

Wright (In Gendler and Hawthorne (Eds.), Conceivability and possibility, 2002) rejects some dominant responses to Kripke’s modal argument against the mind-body identity theory, and instead he proposes a new response that draws on a certain understanding of counterpossibles. This paper offers some defensive remarks on behalf of Lewis’ objection to that argument, and it argues that Wright’s proposal fails to fully accommodate the conceivability intuitions, and that it is dialectically ineffective.     

A Priori Conditionals and the Conceivability of Zombies

Abstract

The conditional analysis of phenomenal concepts, as proposed independently by Hawthorne (2002), Stalnaker (2002) and Braddon-Mitchell (2003), is used to undermine Chalmers's (1996) conceivability argument in a way that is compatible with our having the zombie intuition. The aim of this paper is twofold: (1) To remove current misconceptions concerning how the analysis is to be applied. It will be explained how there are two distinct ways the analysis can be used to undermine the conceivability argument. (2) To employ this exposition to defend the analysis from objections leveled against it by Chalmers (2005) and Alter (2007).     

Conceivability,Explanation, and Defeat

Christopher Hill and Joseph Levine have argued that the conceivabilitiesinvolved in anti-materialist arguments are defeated as evidence ofpossibility. Their strategy assumes the following principle: theconceivability of a state of affairs S constitutes evidence for thepossibility of S only if the possibility of S is the bestexplanation of the conceivability of S. So if there is a betterexplanation of the conceivability of S than its possibility, then theconceivability of S is thereby defeated as evidence of possibility. Hilland Levine proceed to offer alternative explanations of theseconceivabilities, concluding that these conceivabilities are therebydefeated as evidence. However, this strategy fails because theirexplanations generalize to all conceivability judgments concerningphenomenal states. Consequently, one could defend absolutely any theoryof phenomenal states against conceivability arguments in just this way.This result conflicts with too many of our common sense beliefs aboutthe evidential value of conceivability with respect to phenomenalstates. The general moral is that the application of such principles ofexplanatory defeat is neither simple nor straightforward.     

Conceivability and De Re Modal Knowledge

The paper presents a dilemma for both epistemic and non‐epistemic versions of conceivability‐based accounts of modal knowledge. On the one horn, non‐epistemic accounts do not elucidate the essentialist knowledge they would be committed to. On the other, epistemic accounts do not elucidate everyday life de re modal knowledge. In neither case, therefore, do conceivability accounts elucidate de re modal knowledge.     

Physicalism, Conceivability and Strong Necessities

David Chalmers’ conceivability argument against physicalism relies on the entailment from a priori conceivability to metaphysical possibility. The a posteriori physicalist rejects this premise, but is consequently committed to psychophysical strong necessities. These don’t fit into the Kripkean model of the necessary a posteriori, and they are therefore, according to Chalmers, problematic. But given semantic assumptions that are essential to the conceivability argument, there is reason to believe in microphysical strong necessities. This means that some of Chalmers’ criticism is unwarranted, and the rest equally afflicts the dualist. Moreover, given that these assumptions are independently plausible, there’s a general case to be made for the existence of strong necessities outside the psychophysical domain.