Several authors have recently endorsed the thesis that there is what has been called pragmatic encroachment on knowledge—in other words, that two people who are in the same situation with respect to truth-related factors may differ in whether they know something, due to a difference in their practical circumstances. This paper aims not to defend this thesis, but to explore how it could be true. What I aim to do, is to show how practical factors could play a role in (...) defeating knowledge by defeating epistemic rationality—the very kind of rationality that is entailed by knowledge, and in which Pascalian considerations do not play any role—even though epistemic rationality consists in having adequate evidence. (shrink)