a sect of ancient philosophers, founded by Pyrrho, whose distinguishing tenet was, That all things are uncertain and incomprehensible; consequently traries are equally true; and that the mind is never to assent to any thing, but to keep up an absolute hesitancy or indifference. See SCEPTICISM.—The term skeptic, in its original Greek, signifies properly signifies considerative, and insipitive; or, a man who is ever weighing reasons on one side and the other, without ever deciding between them: it is formed from the verb σκεπτόμαι, I consider, look about, deliberate.

Laertius notes, that the followers of Pyrrho had various denominations. From their manner, they were called Pyrrhoniens. From their dogma, aporetic, that is, doubters, of οὐκ εἰσίν, there is doubt: From their suspension and hesitation, sophetic, of σοφεῖν, to say, to keep back: And from their never getting beyond the search of truth, zetetic, seekers.

Plato refutes the great principle of the sceptics thus: When you say that all things are incomprehensible, do you comprehend or conceive that they are thus incomprehensible, or do you not? if you do, then something is comprehensible; if you do not, there is no reason we should believe you, since you do not comprehend your own assertion.