Factual Evidence without Knowledge

A central function of our evidence is to constrain the epistemic rationality of our propositional attitudes. Our knowledge does this. That fact supports Timothy Williamson's contention that our evidence is identical to our knowledge, ‘E=K’. But it is argued here that some true propositions are evidence without being known. Some of them cannot be known; others are contingently not known. Propositions play the rational role of evidence whenever they are clearly true, whether or not they are known.