Aenesidemus. The comprehensive title [Greek: Purrhôneioi
hupotupôseis] was very probably used in general to designate
courses of lectures given by the leaders of the Sceptical
School.

In the opening chapters of the _Hypotyposes_ Sextus undertakes
to define the position and aim of Pyrrhonism.[2] In introducing
his subject he treats briefly of the differences between
philosophical schools, dividing them into three classes; those
which claim that they have found the truth, like the schools of
Aristotle and Epicurus and the Stoics; those which deny the
possibility of finding it, like that of the Academicians; and
those that still seek it, like the Sceptical School. The
accusation against the Academicians, that they denied the
possibility of finding the truth, was one that the Sceptics were
very fond of making. We shall discuss the justice of it later,
simply remarking here, that to affirm the "incomprehensibility
of the unknown," was a form of expression that the Pyrrhonists
themselves were sometimes betrayed into, notwithstanding their
careful avoidance of dogmatic statements.[3]

[1] Diog. IX. 11, 78.

[2] _Hyp._ I. 3, 4.

[3] _Adv. Math._ VIII. 191.

After defining the three kinds of philosophy as the Dogmatic,
the Academic and the Sceptic, Sextus reminds his hearers that he
does not speak dogmatically in anything that he says, but that