26 INTERPRETATION OF NATURE. 



certainly corrupted natural philosophy with logical subtle 

 ties, which were his own creation, as he himself too loudly 

 boasts. 



But to leave him, Plato was, without doubt, a man of 

 loftier genius, and one who aimed also at the knowledge 

 of forms, and used induction universally, not for princi 

 ples only; but with reasoning futile on both sides, since 

 he pursued and accepted vague inductions and abstract 

 forms. And if we consider with attention the writings and 

 habits of this philosopher, we shall find that he took no 

 great interest in natural philosophy, at least so far only as 

 to vindicate his own name and character as a philosopher, 

 or give by its intermixture a certain majesty to his moral 

 and political doctrines. And he adulterated nature as much 

 with theology, as Aristotle with logic ; and, to say the 

 truth, approached as near to the province of the poet as the 

 other to that of the sophist. Now we can draw the doc 

 trines of these two from the very fountain head, their works 

 having survived. 



There is a different estimate to be made of the rest, 

 namely, Pythagoras, Empedocles, Heraclitus, Anaxagoras, 

 Democritus, Parmenis, Zenophanes, and others; because 

 we have received their opinions by means of intermediate 

 writers only, and by tradition, and scattered fragments; 

 so that we must use closer inquisition, with greater scruple 

 of judgment, to make up for the disadvantage of their 

 circumstances. But yet he has been most diligent and 

 watchful to catch every whisper about these opinions, so 

 as to extract whatever can be found referring to them, 

 where they are confuted by Aristotle, or cited by Plato 

 or Cicero ; or in Plutarch s budget, or Laertius lives, or 

 Lucretius poem ; or any other scattered hint or mention : 

 and he has examined them with impartiality and careful 

 judgment. And, first, there is no doubt that, if their 

 opinions were in their own works, they would have greater 

 weight; for the strength of theories lies in a nice and 

 mutual harmony of the parts, and a certain unbroken 

 demonstration; and they* are therefore weakened when 

 uttered in fragments : wherefore he did not make his judg 

 ment of them lightly. 



He found also, among so many opinions, a number of 

 remarks made with some care with regard to the obser 

 vation of nature, and the assigning of causes: and, as 

 commonly happens, some have been more successful than 

 others in different branches. The discoveries and opi 

 nions of Pythagoras alone (though his doctrine of num- 



