Can phenomenal consciousness be given a reductive natural explanation? Exponents of an ‘explanatory gap’ between physical, functional and intentional facts, on the one hand, and the facts of phenomenal consciousness, on the other, argue that there are reasons of principle why phenomenal consciousness cannot be reductively explained: Jackson (1982), (1986); Levine (1983), (1993), (2001); McGinn (1991); Sturgeon (1994), (2000); Chalmers (1996), (1999). Some of these writers claim that the existence of such a gap would warrant a belief in some form of ontological dualism (Jackson, 1982; Chalmers, 1996), whereas others argue that no such entailment holds (Levine, 1983; McGinn, 1991; Sturgeon, 1994). In the other main camp, there are people who argue that a reductive explanation of phenomenal consciousness is possible in principle (Block and Stalnaker, 1999), and yet others who claim, moreover, to have provided such an explanation in practice (Dennett, 1991; Dretske, 1995; Tye, 1995,2000; Lycan, 1996; Carruthers, 2000).

The volitional theory of human action has formed a basis for a prominent account of voluntary behavior since at least Aquinas. But in the twentieth century the notions of will and volition lost much of their popularity in both philosophy and psychology. Gilbert Ryle's devastating attack on the concept of will, and especially the doctrine of volition, has had lingering effects evident in the widespread hostility and skepticism towards the will and volition. Since the 1970s, however, the volitional theory has received some renewed interest in the philosophy of action.

Frederic Fitch's celebrated reasoning to the conclusion that all truths are known can be interpreted as a reductioof the claim that all truths are knowable. Given this, nearly all of the proof's reception has involved canvassing the prospects for some form of verificationism. Unfortunately, debates of this sort discount much of the philosophical import of the proof. In addition to its relevance for verificationism, Fitch's proof is also an argument for the existence of God, one at least as strong as the traditional demonstrations. Perhaps unlike other such proofs, Fitch's also operates as a key lemma in a proof that (if sound) establishes that God can't exist.

While the implications of Fitch's proof are thus very important for our understanding of key concepts in the philosophy of religion, they are also relevant to the proof's traditional reception. With these results, I am able to provide a principled motivation for Neil Tennant's recent defense of a restricted form of verificationism.

How we understand Descartes's physics rests on how we interpret his ontological commitment to individual bodies, and in particular on how we account for their individuation. However, Descartes's contemporaries (notably, Cordemoy and Leibniz) as well as contemporary philosophers (notably, Kenny and Garber) have seen Descartes's account of the individuation of bodies as deeply flawed. In the first part of this paper, I discuss how the various problems and puzzles involved in Descartes's account of the individuation of bodies arise, and the relevance of these problems for his physics. With an eye toward resolving these puzzles, I argue for an interpretation of the Cartesian ontology in which bodies are not individuated by motion but, instead, are mind-dependent. As part of this reading, I demonstrate the sense in which we can clearly and distinctly perceive bodies, and also the senses in which the real, conceptual, and modal distinctions apply to them.

In this paper I offer an interpretation of Malebranche's conception of ideas. This is no easy matter. Malebranche says so many different things about ideas that it is daunting to try to weave them all together. To make matters worse, some of the things he says are not very clear. Worse still, some of the things he says are not obviously consistent with each other or with other Malebranchean doctrines. It is not surprising, therefore, that his account of ideas came under attack from the beginning, and continues to be attacked to this day. It is with trepidation, then, that I offer any interpretation at all. It is with even greater trepidation that I suggest that this interpretation affords Malebranche a clear and coherent theory of ideas, one that is consistent with the rest of his philosophy, has its primitives in the right places, and may even satisfactorily address the common charges laid against him.