Abstract
When a belief is self-fulfilling, having it guarantees its truth. When a belief is self-defeating, having it
guarantees its falsity. These are the cases of “self-impacting” beliefs to be examined below. Scenarios
of self-defeating beliefs can yield apparently dilemmatic situations in which we seem to lack sufficient
reason to have any belief whatsoever. Scenarios of self-fulfilling beliefs can yield apparently dilemmatic
situations in which we seem to lack reason to have any one belief over another. Both scenarios have
been used independently to challenge Evidentialism, on which what we may rationally believe is all
and only what fits our current evidence. Here we tie the two scenarios together and explore what a
knowledge-sensitive evidentialist approach to one implies for the other.