It will be apposite to consider next the aim of the Sceptical persuasion. Now an aim is that for the sake of which everything is done or considered, while it is not itself done or considered for the sake of anything else. Or: an aim is the final object of desire. Up to now we say the aim of the Sceptic is tranquility in matters of opinion and moderation of feeling in matters forced upon us. For Sceptics began to do philosophy in order to decide among appearances and to apprehend which are true and which false, so as to become tranquil; but they came upon equipollent dispute, and being unable to decide this they suspended judgment. And when they suspended judgment, tranquility in matters of opinion followed fortuitously.
Sextus Empiricus, Outlines of Scepticism. Translated by Annas and Barnes.