position) but rather of providing an account of sceptical arguments that
entitles
us to persist in them in the face of those arguments. A straight
forward response to scepticism
would be to try to show that sceptical ar
guments are unsound, either because they involve an incorrect premise
or assumption or because the inferences they involve are invalid. For in
stance, a familiar
kind of sceptical argument adduces the mere possibil
ity that one is, say, dreaming or a brain in a vat, and infers from this that
one does not know, say, that one has teeth. Many philosophers have ar
gued,
on various grounds, that these alleged possibilities are not genuine
ones; while others have denied, also on various grounds, that the admis
sion
of these outre possibilities is incompatible with our common-sense
convictions
about what we know.
What is striking, though, is the lack of consensus about these kinds of
straightforward responses to scepticism. While each
has its committed
advocates,
many if not most philosophers reject each particular response
in favor of a different one, at the same time joining in the consensus that
the conclusions of sceptical arguments should be rejected. The case is
quite different
with other long-standing philosophical issues. Consider
the perennial disputes over realism,
broadly speaking the view that the
world has an objective character independent of our beliefs and theories
about it which makes those beliefs and theories true or false. Philosophers
are
divided in their attitudes toward it, and I think it is safe to say that
there is no consensus either in favor of or against realism in some form.
But
among those drawn to one side of the dispute or the other, there is a
fair
amount of agreement about what is wrong with arguments for the
other side. Antirealists, for example,
tend to accept the familiar criticisms
of arguments for realism
that appeal to the success of science, while those
drawn to realism tend to agree about the fallacies in Berkeley's arguments
for immaterialism. The fact that the consensus for rejecting scepticism is
not mirrored in a consensus about what is wrong with the arguments for
it is, I believe, a striking datum.
It is, of course, a datum and not an argu
ment. But I
think it should at least lead us to question whether a straight
forward response to scepticism
and sceptical arguments is liable to
succeed.
In the absence of a straightforward response to it, philosophical scep
ticism might be thought, as Stephen Shiffer suggests, to present a
kind of
paradox,
in that reasoning that does not seem fallacious leads to conclu
sions inconsistent
with propositions we regard as obviously true.2 This
2. Stephen Shiffer, "Contextualist Solutions to Scepticism," Proceedings of the Aristotelian
Society n.s. 96 (1996), 317-333.
2 Scepticism, Knowledge, and Forms of Reasoning