Nozick analyzes fundamental issues, such as the identity of the self, knowledge and skepticism, free will, the foundations of ethics, and the meaning of life.

In these challenging pages, Unger argues for the extreme skeptical view that, not only can nothing ever be known, but no one can ever have any reason at all for anything. A consequence of this is that we cannot ever have any emotions about anything: no one can ever be happy or sad about anything. Finally, in this reduction to absurdity of virtually all our supposed thought, he argues that no one can ever believe, or even say, that anything is (...) the case. (shrink)

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

1. I am going to work with an idea from Sellars, that knowledge—at least as enjoyed by rational animals—is a certain sort of standing in the space of reasons. My concern is a familiar philosophical dialectic, which I shall approach in terms of what happens to the Sellarsian idea when the image of standings in the space of reasons undergoes a certain deformation. That it is a deformation is something we can learn from how unsatisfactory the familiar dialectic is.

In his recent Knowledge and its Limits, Timothy Williamson argues that no non-trivial mental state is such that being in that state suffices for one to be in a position to know that one is in it. In short, there are no “luminous” mental states. His argument depends on a “safety” requirement on knowledge, that one’s confident belief could not easily have been wrong if it is to count as knowledge. We argue that the safety requirement is ambiguous; on one (...) interpretation it is obviously true but useless to his argument, and on the other interpretation it is false. (shrink)