CAUSE OF ITS FAILURE. So 



would go near to madness to hold such opinions in practice (for no 

 one was ever so mad as to think fire and ice to be one), Leucippus, 

 therefore, pursued a line of reasoning which was in accordance with 

 sensation, and which was not irreconcilable with the production and 

 decay, the motion and multitude of things." It is obvious that the 

 school to which Leucippus belonged (the Eclectic) must have been, at 

 least in its origin, strongly impressed with the necessity of bringing its 

 theories into harmony with the observed course of nature. 



2. Nor was this recognition of the fundamental value of experience 

 a mere profession. The Greek philosophy did, in its beginning, pro- 

 ceed upon observation. Indeed it is obvious that the principles which 

 it adopted were, in the first place, assumed in order to account for 

 some classes of facts, however imperfectly they might answer their 

 purpose. The principle of things seeking their own places, was 

 invented in order to account for the falling and floating of bodies. 

 Again, Aristotle says, that heat is that which brings together things 

 of the same kind, cold is that which brings together things whether of 

 the same or of different kinds : it is plain that in this instance he 

 intended by his principle to explain some obvious facts, as the freezing 

 of moist substances, and the separation of heterogeneous things by 

 fusion; for, as he adds, if fire brings together things which are akin, it 

 will separate those which are not akin. It would be easy to illustrate 

 the remark further, but its truth is evident from the nature of the 

 case ; for no principles could be accepted for a moment, which were 

 the result of an arbitrary caprice of the mind, and which were not in 

 some measure plausible, and apparently confirmed by facts. 



But the works of Aristotle show, in another way, how unjust it 

 would be to accuse him of disregarding facts. Many large treatises of 

 his consist almost entirely of collections of facts, as for instance, those 

 " On Colors," " On Sounds," and the collection of Problems to which 

 we have already referred ; to say nothing of the numerous collection 

 of facts bearing on natural history and physiology, which form a great 

 portion of his works, and are even now treasuries of information. A 

 moment's reflection will convince us that the physical sciences of our 

 own times, for example, Mechanics and Hydrostatics, are founded 

 almost entirely upon facts with which the ancients were as familiar as 

 we are. The defect of their philosophy, therefore, wherever it may lie, 

 consists neither in the speculative depreciation of the value of facts. 

 nor in the practical neglect of their use. 



3. Nor again, should we hit upon the truth, if we were to say thai 



