Scanned text contains errors.
made the discovery of causes the highest object of scientific investigations. He once said, that he preferred the discovery of a true cause to the pos-sesssion of the kingdom of Persia. (Dionys. Alex. ap. Euseb. Praep. Evang. xiv. 27.) We must not, therefore, take the word chance (tux'*?) ^n its vulgar acceptation, (Brandis, 1. c. p. 319.) Aristotle understood Democritus rightly in this respect (Phys. Auscult. ii. 4, p. 196. 11; Simplic. fol. 74), as he generally valued him highly, and often says of him, that he had thought on all subjects, searched after the first causes of phaenomena, and endeavoured to find definitions. (De Generat. et Corrupt. i. 2, 8, Metapli. M. 4, Pliys. ii. 2, p. 194, 20, de Part. Anim. i. p. 642, 26.) The only tiling for which he censures him, is a disregard for teleologi-cal relations, and the want of a comprehensive system of induction. (DeRespir. 4, de Generat. Anim. v. 8.) Democritus himself called the common notion of chance a cover of human ignorance (-Trpo'^a-<riv I8ii]s avoif}s\ and an invention of those who were too idle to think. (Dionys. ap. Euseb. Praep. Evang. xiv. 27; Stob. Eclog. Etli. p. 344.)
Besides the infinite number of atoms existing in infinite space, Democritus also supposed the existence of an infinite number of worlds, some of which resembled one another, while others differed from one another, and each of these worlds was kept together as one thing by a sort of shell or skin. He derived the four elements from the form of the
atoms predominating in each, from their quality,
and their relations of magnitude. In deriving individual things from atoms, he mainly considered the qualities of warm and cold. The warm or fire-like he took to be a combination of fine, spheric, and very movable atoms, as opposed to the cold and moist. His mode of proceeding, however, was, first carefully to observe and describe the phaenomena themselves, and then to attempt his atomistic explanation, whereby he essentially advanced the knowledge of nature. (Papencordt, /. c. p. 45, &c.; Brandis, I. c. p. 327.) He derived the soul, the origin of life, consciousness, and thought, from the finest fire-atoms (Aristot. de Anim. i. 2, ed. Trendelenburg); and in connexion with this theory he made very profound physiological investigations. It was for this reason that, according to him, the soul while in the body acquires perceptions and knowledge by corporeal contact, and that it is affected by heat and cold. The sensuous perceptions themselves were to him affections of the organ or of the subject perceiving, dependent on the changes of bodily condition, on the difference of the organs and their quality, on air and light. Hence the differences, e. g., of taste, colour, and temperature, are only conventional (Sext. Empir. adv. Math. vii. 135), the real cause of those differences being in the atoms.
It was very natural, therefore, that Democritus described even the knowledge obtained by sensuous perception as obscure ((tkotlvjv Kpicfiv). A clear and pure knowledge is only that which has reference to the true principles or the true nature of things, that is, to the atoms and space. But knowledge derived from reason was, in his opinion, not specifically different from that acquired through the senses; for conception and reflection were to him only effects of impressions made upon the senses; and Aristotle, therefore, expressly states, that Democritus did not consider mind as something peculiar, or as a power distinct from the soul
or sensuous perception, but that he considered knowledge derived from reason to be sensuous perceptions. (De Anim. i. 2. p. 404,27.) A purer and higher knowledge which he opposed to the obscure knowledge obtained through the medium of the senses, must therefore have been to him a kind of sensation, that is, a direct perception of the atoms and of space. For this reason he assumed the three criteria (itpiTripia) : a. Phaenomena as criteria for discovering that which is hidden : b. Thought as a criterion of investigation: and c. Assertions as criteria of desires. (Sext. Emp. adv. Math. vii. 140 ; Brandis, L c. p. 334.) Now as Democritus acknowledged the uncertainty of perceptions, and as he was unable to establish a higher and purely spiritual source of knowledge as distinct from perceptions, we often find him complaining that all human knowledge is uncertain, that in general either nothing is absolutely true, or at least not clear to us (aSf]\ov^ Aristot. Metapli,, F. 5), that our senses grope about in the dark (sensus tenebricosi^ Cic. Acad. iv. 10, 23), and that all our views and opinions are subjective, and come to us only like something epidemic, as it were, with the air which we breathe. (Sext. Emp, adv. Math. vii. 136, 137, viii. 327, Hypotyp. i. 213; Diog. Lae'rt. ix. 72, Ire?; 5' ovdev i'5/xez/, e*> fivdtp yap tf dA?50eia, which Cicero translates in prof undo veritatem esse.)
In his ethical philosophy Democritus considered the acquisition of peace of mind (evdv^ia) as the end and ultimate object of our actions. (Diog. Lae'rt. ix. 45 ; Cic. de Fin. v. 29.) This peace, this tranquillity of the mind, and freedom from fear (tyoGos and $ei(n$aip.ovia} and passion, is the last and fairest fruit of philosophical inquiry. Many of his ethical writings had reference to this* idea and its establishment, and the fragments relating to this question are full of the most genuine practical wisdom. Abstinence from too many occupations, a steady consideration of one's own powers, which prevents our attempting that which we cannot accomplish, moderation in prosperity and misfortune, were to him the principal means of acquiring the evdviJ.ia. The noblest and purest ethical tendency, lastly, is manifest in his views on virtue and on good. Truly pious and beloved by the gods, he says, are only those who hate that which is wrong (ocrois exOpov to aSi/mr). The purest joy and the truest happiness are only the fruit of the higher mental activity exerted in the endeavour to understand the nature of things, of the peace of mind arising from good actions, and of a clear conscience. (Brandis, I. c. p. 337.)
The titles of the works \vhich the ancients ascribed to Democritus may be found in Diogenes Laertius. We find among them : 1. Works of ethics and practical philosophy. 2. On natural science. 3. On mathematics and astronomy. 4. On music and poetry, on rhythm and poetical beauty (Bode, Gesch. der Hellen. Diclitkunst. i. p. 24, &c.), and on Homer. 5. Works of a linguistic and grammatical nature; for Democritus is one of the earliest Greek philosophers that made language the subject of his investigations. (Lersch, Spraeh-pJiilosophie der Alten^ i. p. 13, &c.) 6. Works on medicine, 7- On agriculture. 8. On painting. 9. On mythology, history, &c. He had even occupied himself, with success, with mechanics; and Vitruvius (Praef. lib. vii.; comp. Senec. Episi. 90) ascribes to him certain inventions, for example,