CHAP. XXII.] CONSTITUTION OF THE INTELLECT. 413 



of "strife" and "friendship;" and the theory of Leucippus,* 

 which resolved all existence into the two elements of a. plenum 

 and a vacuum, are of this nature. The famous comparison of the 

 universe to a lyre or a bow,t its "recurrent harmony" being the 

 product of opposite states of tension, betrays the same origin. 

 In the system of Pythagoras, which seems to have been a combi- 

 nation of dualism with other elements derived from the study of 

 numbers, and of their relations, ten fundamental antitheses are 

 recognised: finite and infinite, even and odd, unity and multitude, 

 right and left, male and female, rest and motion, straight and 

 curved, light and darkness, good and evil, the square and the 

 oblong. In that of Alcmaeon the same fundamental dualism is 

 accepted, but without the definite and numerical limitation with 

 which it is connected in the Pythagorean system. The grand 

 development of this idea is, however, met with in that -ancient 

 Manichgean doctrine, which not only formed the basis of the re- 

 ligious system of Persia, but spread widely through other regions 

 of the East, and became memorable in the history of the Christian 

 Church. The origin of dualism as a speculative opinion, not 

 yet connected with the personification of the Evil Principle, but 

 naturally succeeding those doctrines which had assumed the 

 primal unity of Nature, is thus stated by Aristotle : " Since 

 there manifestly existed in Nature things opposite to the good, 

 and not only order and beauty, but also disorder and deformity ; 

 and since the evil things did manifestly preponderate in number 

 over the good, and the deformed over the beautiful, some one 

 else at length introduced strife and friendship as the respective 

 causes of these diverse phsenomena/'J And in Greece, indeed, 

 it seems to have been chiefly as a philosophical opinion, or as an 

 adjunct to philosophical speculation, that the dualistic theory ob- 

 tained ground. The moral application of the doctrine most in 



* Arist. Met. i. 4, 9. 



f TrttXtvrpoTrog apuovirj OKWQ Trtp TOOV KO.I \vprjg. Heraclitus, quoted in 

 Origenis Philosophumena, ix. 9. Also Plutarch, De hide et Osiride. 



J 'Erst 5e KCU ravavria TOIQ ayaOolQ tvovra fQaivtro iv Ty Qvaii, teal ov 

 f.i6vov TO.%IQ Kcii TO KctXbv eiXXd ical draia /cat TO aiaxpov, ical TrXtt'w TO. Kaica 

 TU>V aya9it>v icai TO. 0auXa TWV KO\U>V, OVTIDQ dXXof TIQ tyiKiav tiarjt'fyics ical vfl- 

 KOQ, fKanpov tKciTtptoiV ct'iTiov TOVTWV. Arist. Metaphysicct, I. 4. 



Witness Aristotle's well-known derivation of the elements from the quali- 



