ABSTRACT When does an agent possess a proposition P as evidence? According to Timothy Williamson, the answer is when, and only when, they know that P . Call this view E = K. In this article, I point out an unwanted consequence of E = K, which is that people who suffer from anxiety have impoverished empirical evidence due to their anxiety. Although anxiety can manifest in a variety of ways and to different degrees, I take it that in some cases a person's anxiety functions in a way that prevents a person from believing in accordance with their empirical evidence. However, E = K has trouble explaining the descriptive and normative dimensions of a case like this, because the view implies that whenever an agent's anxiety prevents them from outright believing a proposition this ipso facto deprives them of empirical evidence.
Rhys Borchert (Mon,) studied this question.