Luis Rosa

Epistemologists take themselves to disagree about whether there are situations where it is rational for one to believe that p and rational for one to believe that one’s evidence does not support p (rational akrasia). The embedded sentence ‘one’s evidence does not support p’ can be interpreted in two ways, however, depending on what the semantic contribution of ‘one’s evidence’ is taken to be. ‘One’s evidence’ might be seen as a sheer indexical or as a descriptive singular term. The first interpretation makes the relevant kind of rational akrasia impossible, whereas the second one makes it possible. But the proposition that is taken to be expressed by ‘one’s evidence does not support p’ by each of these interpretations is not the same. We thus have a rational reconstruction of views that are labeled as being for and against the possibility of rational akrasia according to which they do not really contradict each other.

In this paper I deal with epistemological issues that stem from the hypothesis that reasoning is not only a means of transmitting knowledge from premise-beliefs to conclusion-beliefs, but also a primary source of knowledge in its own right. The idea is that one can gain new knowledge on the basis of suppositional reasoning. After making some preliminary distinctions, I argue that there are no good reasons to think that purported examples of knowledge grounded on pure reasoning are just examples of premise-based inferences in disguise. Next, I establish what kinds of true propositions can to a first approximation be known on the basis of pure reasoning. Finally, I argue that beliefs that are competently formed on the basis of suppositional reasoning satisfy both externalist and internalist criteria of justification.

How does rationality bind the agnostic, that is, the one who suspends judgment about whether a given proposition is true? In this paper I explore two alternative ways of establishing what the rational requirements of agnosticism are: the Lockean–Bayesian framework and the doxastic logic framework. Each of these proposals faces strong objections. Fortunately, however, there is a rich kernel of requirements of agnosticism that are vindicated by both of them. One can then endorse the requirements that belong to that kernel without thereby committing oneself to the problematic implications that stem from either of the aforementioned proposals.