MONOTHEISM AND RELIGIOUS EXPERIENCE 221(P4) If a person S has an experience E which, if reliable, is a matter of
being aware of an experience-independently existing item X, and E
is not canceled or counterbalanced or compromised or contradicted,
then S’s having E gives S evidence that X exists.
If Mary knows of the proof or the physical conditions and laws, she is
justified in not taking her experience to be evidence that she sees a real tiger.
Yet again, suppose that someone proves, or gives us superb reason for
believing, that there is a Tiger Deceiver who has complete power relative to
the production of as-if-there-is-a-tiger perceptions and causes them only
when there are no tigers. Thus, while we do not know whether there are
tigers or not, we do know that all our experiences that seem to tell us that
there are tigers are fakes. Under these conditions, let us say, Mary’s as-if-
there-is-a-tiger-in-the-garden experience is confuted. Thus (P4) yields pride
of place to:
(P5) If a person S has an experience E which, if reliable, is a matter
of being aware of an experience-independently existing item
X, and E is not canceled or counterbalanced or compromised or
contradicted or confuted, then S’s having E gives S evidence
that X exists.
If Mary has good reason for thinking that there is a Tiger Deceiver, she is
justified in not taking her experience as evidence that she sees a tiger.
The notion of a Tiger Deceiver is one way of expressing the idea that what
we call perceptions of tigers are universally illusory. This idea is distinct
from the fact that it is logically possible that all perceptions of tigers are
deceptive – that there never is a tiger when one seems to perceive one. That is
a fact, just as it is a fact that it is logically possible that no perceptions of
tigers are deceptive – that there always is a tiger that one sees when one
seems to perceive one. The logical possibility of universal correctness, and
the logical possibility of universal incorrectness, of tiger perceptions are not
in dispute; neither idea is what the Tiger Deceiver idea concerns. That idea
concerns the actual universal incorrectness of perceptions of tigers.
Finally, consider the neither lucid nor empty notion of a kind of
experience. Let all sensory experiences be of the same kind, all introspective
experiences be of the same kind, all moral experiences be of the same kind,
all aesthetic experiences be of the same kind, presumably with various sub-
kinds within each kind. Consider claims:
(K) If it is logically possible that an experience E of kind K provide
evidence in favor of existential proposition P, then it is logically
possible that an experience E* of kind K provide evidence against P.