INTRODUCTION-. 9 



world, and all the phenomena revealed to us by sensuous 

 perception. After men had for a long time, in accordance 

 with the earliest ideas of the Hellenic people, venerated the 

 agency of spirits, embodied in human forms, 10 in the creative, 

 changing, and destructive processes of nature ; the germ of a 

 scientific contemplation developed itself in the physiological 

 fancies of the Ionic school. The first principle of the origin 

 of things, the first principle of all phenomena, was referred 

 to two causes 11 either to concrete material principles, the so- 

 called elements of Nature, or to processes of rarefaction and 

 condensation, sometimes in accordance with mechanical, some- 

 times with dynamic views. The hypothesis of four or five 

 materially differing elements, which was probably of Indian 

 origin, has continued from the sera of the didactic poem of 

 Empedocles, down to the most recent times, to imbue all opi- 

 nions on natural philosophy a primeval evidence and monu- 

 ment of the tendency of the human mind to seek a generaliza- 

 tion and simplification of ideas, not only with reference to 

 the forces, but also to the qualitative nature of matter. 



In the latter period of the development of the Ionic phy- 

 siology, Auaxagoras of ClazomenaB advanced from the pos- 

 tulate of simply dynamic forces of matter, to the idea of a 

 spirit independent of all matter, uniting and distributing the 



10 In the memorable passage (Metdph. xii. 8. p. 1074, 

 Bekker.) in which Aristotle speaks of " the relics of an earlier 

 acquired and subsequently lost wisdom," he refers with extra- 

 ordinary freedom and significance to the veneration of phy- 

 sical forces, and of gods in human forms: "much," says 

 he, " has been mythically added for the persuasion of the 

 multitude, as also on account of the laws and for other useful 

 ends." 



1 The important difference in these philosophical direc- 

 tions rporroi, is clearly indicated in Arist. Phys. Auscult. 

 1. 4, p. 187, Bekk. (Compare Brandisin the Rhein. Museum 

 fur Phikloyie, Jahrg. iii. s. 105.) 



