However, one of the most celebrated of the Sceptics, whose works we still in great measure possess, and who for us is by far the most important writer upon Scepticism, because he gives us detailed accounts of this philosophy, is Sextus Empiricus, of whose life unfortunately as good as nothing is known. He was a physician, and that he was an empirical physician, who did not act according to theory but in accordance with what appears, his name tells us. He lived and taught about the middle of the second century after Christ.[191] His works are divided into two parts: first, his _Pyrrhoniæ Hypotyposes_, in three books, which give us somewhat of a general presentation of Scepticism, and secondly his books _adversus Mathematicos_, _i.e._ against scientific knowledge generally, and more especially against the geometricians, arithmeticians, grammarians, musicians, logicians, physicists, and moral philosophers. There were in all eleven books, six of which are actually directed against mathematicians, but the other five against the philosophers. The distinction between the Academy and Scepticism was a matter as to which the Sceptics exercised themselves much. The New Academy really bordered so closely upon Scepticism, that the Sceptics had enough to do to dissociate themselves from it, and in the Sceptic school a long and important battle raged as to whether Plato, and subsequently the New Academy, belonged to Scepticism or not;[192] in the course of this we also see that Sextus did not really know what to make of Plato. The Sceptics are, on the whole, very careful to distinguish their own from other systems. Sextus (Pyrrh. Hyp. I. c. 1, §§ 1-4) distinguishes three philosophies: “He who seeks an object must either find it or deny that it can be found, or persevere in the search. Now the same holds good with philosophic investigations; some assert that they have found the truth; others deny that it can be grasped; a third set are still engaged in search. The first, like Aristotle, Epicurus, the Stoics, and others, are the so-called Dogmatists; those who assert incomprehensibility are the Academicians; the Sceptics still continue to seek. Hence there are three philosophies: the Dogmatic, the Academic and the Sceptical.” For this reason, the Sceptics called themselves the seekers (ζητητικοί), and their philosophy the seeking (ζητητική).[193] However, the distinction between Scepticism and the New Academy rests in the form of expression only, and is thus not a great one: indeed it is founded only on the mania of the Sceptics to cut off and to shun any sort of assertive statement. Sextus (Pyrrh. Hyp. I. c. 7, § 13; c 10, §§ 19-20) says: “The Sceptic does not dogmatize, but only assents to the affections into which he is impelled, not of his own will, by the conceptions; thus, if for example, he is warm or cold, he will certainly not say, I seem not to be cold or warm. But if it be asked if the subject is as it appears, we allow appearance (φαίνεσθαι); yet