On the contrary, it is one of the least rational places to stand.
The question seems to tie skepticism with rationality, which seems to me an incorrect definition. Skepticism is a tool in the philosophers toolbox and reason is the mighty pillar on which the entire project of philosophy rests. Certainly it is often rational to be skeptical, but to imagine that skepticism is always or even usually the most rational course of action seems, well, foolish.
Philosophical Skepticism finds it's basis on the idea that reason is founded on some set of axioms which are not themselves provable. Even Descartes' cogito ergo sum must be accepted without proof, since it amounts to a circular argument. (The first term assumes the existence of a thinker, which is the conclusion the argument tries to reach.) But there are other tools in the philosopher's shed besides the hammer of skepticism. We could, for instance, simply agree on some common set of axioms on which to base our dialog.
Extreme skepticism is in fact self-defeating. According the the Wikipedia article linked in the question, "philosophical skepticism is an approach that denies the possibility of knowledge". Therefore philosophical skepticism can not claim even that philosophical skepticism is correct. Therefore a critic of philosophical skepticism can not be compelled to accept any of its claims.
Here's an interesting comment this answer received:
If you believe that no truth is safe from doubt, you're a skeptic. – philosodad
Let's call that statement (a)
. I believe that it is mistaken and I'll use this space to explain why.
Now this statement is clearly true by definition:
(b) If you're a skeptic, you believe that no truth is safe from doubt.
(For the moment, we'll ignore the various types of skeptics and stick with this concise definition.) It's clear that (a)
does not follow from (b)
, so proving (a)
requires more work. But immediately, if you start with (b)
, there's a potential contradiction: according to (b)
a skeptic does not believe that (b)
is safe from doubt and it's possible that it's not true. Which leaves me stuck before I even get started. In fact, no truth may be derived from (b)
that is safe from doubt if you are a skeptic.
But my answer assumes doubt and skepticism hold a different place in philosophy than a starting point. Rather, I hold that a good set of axioms should include Cromwell's Rule:
(c) I beseech you, in the bowels of Christ, think it possible you may be mistaken.
- Oliver Cromwell
As a starting point, (c)
is not better than (b)
. But it doesn't claim to be a starting point. In fact, you have to already believe something is true before you can begin to apply Cromwell's Rule. There are some axioms that are so likely to be true that we can safely say they are true. But according to (c)
, we must be prepared to change our minds given sufficient evidence. Suppose we hold, for instance:
(d) All participants on philosophy.stackexchange.com
are human.
I'd say (d)
is true. But if one of the participants reveals that they are in fact some very sophisticated AI designed to save money at universities by replacing philosophy professors with computers and if it presented sufficient evidence, I'd have to reconsider (d)
. And if I didn't, I'd violate (c)
.
Am I a skeptic, therefore? By no means! But I do find skepticism to be a useful tool for combating misplaced certainty.