was
David Hume, who attempted to show that the most fundamental categories
of thought, such as substance and causality, are illusory, and thereby
to undermine the fabric of knowledge. Subjectivism usually ends in
scepticism. For knowledge is the relation of subject and object, and
to lay exclusive emphasis upon one of its terms, the subject, ignoring
the object, leads to the denial of the reality of everything except
that which appears to the subject. This was so with the Sophists. And
now we have the reappearance of a similar {362} phenomenon. The
Sceptics, of whom we are about to treat, made their appearance at
about the same time as the Stoics and Epicureans. The subjective
tendencies of these latter schools find their logical conclusion in
the Sceptics. Scepticism makes its appearance usually, but not always,
when the spiritual forces of a race are in decay. When its spiritual
and intellectual impulses are spent, the spirit flags, grows weary,
loses confidence, begins to doubt its power of finding truth; and the
despair of truth is scepticism.

Pyrrho.

The first to introduce a thorough-going scepticism among the Greeks
was Pyrrho. He was born about 360 B.C., and was originally a painter.
He took part in the Indian expedition of Alexander the Great. He left
no writings, and we owe our knowledge of his thoughts chiefly to his
disciple Timon of Phlius. His philosophy, in common with all
post-Aristotelian systems, is purely practical in its outlook.
Scepticism, the denial of knowledge, is not posited on account of its
speculative interest, but only because Pyrrho sees in it the road to
happiness, and the escape from the calamities of life.

The proper course of the sage, said Pyrrho, is to ask himself three
questions. Firstly, he must ask what things are and how they are
constituted; secondly, how we are related to these things; thirdly,
what ought to be our attitude towards them. As to what things are, we
can only answer that we know nothing. We only know how things appear
to us, but of their inner substance we are ignorant. The same thing
appears differently to different people, and therefore it is {363}
impossible to know which opinion is right. The diversity of opinion
among the wise, as well as among the vulgar, proves this. To every
assertion the contradictory assertion can be opposed with equally good
grounds, and whatever my opinion, the contrary opinion is believed by
somebody else who is quite as clever