Robert Pasnau

Medieval epistemology begins as ideal theory: when is one ideally situated with regard to one's grasp of the way things are? Taking as their starting point Aristotle's Posterior Analytics, scholastic authors conceive of the goal of cognitive inquiry as the achievement of scientia, a systematic body of beliefs, grasped as certain, and grounded in demonstrative reasons that show the reason why things are so. Obviously, however, there is not much we know in this way. The very strictness of this ideal in fact gives rise to a body of literature on how Aristotle's framework might be relaxed in various ways, for certain specific purposes. In asking such questions, scholastic authors are in effect pursuing the project of social epistemology, by trying to adapt their ideal theory to the circumstances of everyday life

When objects are illuminated, the light they reflect does not simply bounce off their surface. Rather, that light is entirely reabsorbed and then reemitted, as the result of a complex microphysical event near the surface of the object. If we are to be physicalists regarding color, then we should analyze colors in terms of that event, just as we analyze heat in terms of molecular motion, and sound in terms of vibrations. On this account, colors are not standing properties of objects, but events, or (more cautiously) properties associated with events. Accordingly, objects in the dark are no more colored than a turned-off stove is hot. Such an account requires rejecting some of what folk ordinarily say about color, but this is the most coherent version of color physicalism.

Reflection on the history of skepticism shows that philosophers have often conjoined as a single doctrine various theses that are best kept apart. Some of these theses are incredible – literally almost impossible to accept – whereas others seem quite plausible, and even verging on the platitudinous. Mixing them together, one arrives at a view – skepticism – that is as a whole indefensible. My aim is to pull these different elements apart, and to focus on one particular strand of skepticism that deserves sustained and respectful attention. The strand I have in mind I will refer to as epistemic defeatism. Roughly, in its most global form, it is the view that, in the final analysis, we have no good evidence for the truth of any proposition. Working through various historical texts, I attempt to untangle epistemic defeatism from neighboring views, and in particular to establish its independence from questions about knowledge. Having thus established the view's autonomy, I turn to the options for self-consciously accepting defeat. One may despair or one may have faith. But I will ultimately propose that the most attractive option – the option that preserves the most of our epistemic integrity – is to have hope.

A theory of human nature must consider from the start whether it sees human beings in fundamentally biological terms, as animals like other animals, or else in fundamentally supernatural terms, as creatures of God who are like God in some special way, and so importantly unlike other animals. Many of the perennial philosophical disputes have proved so intractable in part because their adherents divide along these lines. The friends of materialism, seeing human beings as just a particularly complex example of the sort of complex organic structure found everywhere on Earth, suppose that we are ultimately constituted out of just the same material from which squirrels and rabbits are made. The friends of dualism, instead, think that such a story can hardly do justice to what is special about human nature. Likewise, the friends of a libertarian, robustly non-deterministic conception of free will see something special in human spontaneity and moral responsibility. To their opponents, human beings operate on the same principles, albeit more complex, as do squid and plankton. These and other such disputes need not divide along religious lines. One may oppose naturalism without embracing a supernatural theistic perspective; one might, for instance, think it simply a matter of fact that human beings are fundamentally unlike other biological organisms, but yet not suppose we are made that way by any higher power. Conversely, the theist may think it part of the divine plan to have made human beings as nothing more than the most complex of biological organisms, constituted out of the same stuff and constrained by the same laws. So although the choice I have described between two perspectives –

A theory of how rationally to respond to disagreement requires a clear account of how to measure comparative reliability. Such an account faces a Generality Problem analogous to the well-known problem that besets reliabilist theories of knowledge. But whereas the problem for reliabilism has proved recalcitrant, I show that a solution in the case of disagreement is available. That solution is to measure reliability in the most fine-grained way possible, in light of all the circumstances of the present disagreement, but behind a veil that precludes taking into account which views are one's own. This resolves two of the leading obstacles to understanding what disagreement rationally requires: the objection from neglecting the evidence, and the objection from absurd disagreements. Appealing to the contractualist's veil of ignorance also sheds an interesting light on the very different ways in which disagreement gets resolved in epistemology versus political theory. The comparison raises troubling questions on both sides, because it seems doubtful that the political theorist's usual strategies are epistemically rational, and it seems doubtful that the epistemologist's usual strategies are sufficiently attuned to what we care about

It is important to distinguish between two ways in which God might be timelessly eternal: eternality as being wholly outside of time, versus the sort of timelessness that consists in lacking temporal parts, and so existing “all at once.” A prominent but neglected historical tradition, most clearly evident in Anselm, advocates putting God in time, but in an all-at-once sort of way that makes God immune to temporal change. This is an intrinsically plausible conception of divine eternality, which also sheds light on the modern dispute over the endurance or perdurance of material objects.