  Assume for the sake of illustration that what one is justified in believing does in fact depend upon the space of alternative hypotheses of which one is aware: as new hypotheses are introduced, one's justification for believing already proposed hypotheses changes. Given the Evidentialist thesis that differences in justification are always underwritten by differences in evidence, it follows that a complete specification of one's evidence at any given time will make reference to the set of hypotheses which one is aware of at that time. This is an example of the way in which intuitive judgments about what individuals are justified in believing in certain circumstances, when coupled with a commitment to Evidentialism, can drive one's theory of evidence (i.e., make a difference to which items one classifies as ‘evidence’ in one's theorizing).