Mark Heller

René Descartes, one of the dominant figures in the history of philosophy, has been accused of one of the most obvious mistakes in the history of philosophy — the so-called cartesian circle. It is my goal in this paper to arrive at an understanding of Descartes's work that attributes to him a theory that should be of philosophical interest to contemporary epistemologists, is consistent with, and suggested by, the actual text, and avoids the circle.I begin with a brief explanation of the supposed circle. In his search for absolute certainty Descartes requires that in order for a proposition to be an instance of knowledge it must be indubitable for the knower, and in order for it to be indubitable for the knower she must be able to eliminate any possibility of the belief's being false. It is to provide a means to satisfy this requirement that Descartes proposes the principle whatever is clearly and distinctly perceived cannot be false.And it seems that Descartes's defense of CD traps him in the circle.

In 1962 Hilary Putnam forced us to face the possibility of robot cats. More than twenty years later Daniel Dennett found himself doing battle with mad scientists and other “bogeymen.” Though these two examples are employed in different philosophical arena, there is an important connection between them that has not been emphasized. Separating the concept associated with a kind term from the extension of that term, as Putnam and others have urged, raises the possibility of accepting counterexamples to compatibilistic analyses without rejecting compatibilism. Even if no compatibilist analysis of our concept of free action is acceptable, a compatibilist account of the essential nature of free action may be.

The Donkey Problem (as I am calling it) concerns the relationship between more and less fundamental ontologies. I will claim that the moral to draw from the Donkey Problem is that the less fundamental objects are merely conventional. This conventionalism has consequences for the 3D/4D debate. Four-dimensionalism is motivated by a desire to avoid coinciding objects, but once we accept that the non-fundamental ontology is conventional there is no longer any reason to reject coincidence. I therefore encourage 4Dists to become even more radical—embrace the Donkey Problem’s conventionalism and deflate the debate between 3Dists and 4Dists.

The conditional analysis of ability statements has many versions. In this paper I will deal with the version which claims that ‘x can do y’ is equivalent to ‘if x were to choose to do y, then x would do y.’ However, my comments should be equally applicable to any analysis of ability statements that can properly be called a version of the conditional analysis. The intuition behind the conditional analysis is that what it is for one to be able to do something is for one's choice to be effective. To have an ability to do y is for it to be true that one's choosing to do y would be effective - one's choosing to do y would result in one's doing y. But this intuition is not captured by the conditional analysis in its standard form, and a restriction is needed to mend this defect. This restriction is based on a distinction among counterfactual conditionals.