216 Geographical Collections. 



passionate soul is placed in the breast, and its principal seat is the heart. By 

 its impetuosity it would tend to predominate over the reasonable soul. To pre- 

 vent this, the communications between the one and the other have been rendered 

 difficult by the contraction of the neck. The gross or vegetative soul, occupied 

 with material objects, resides in the lower beUy. The two latter souls have each 

 their moderator. The lungs, cooled by the air which they receive, are placed 

 near the heart ; the liver is placed in the neighbourhood of the stomach, the prin- 

 cipal seat of the gross soul, and has near it the spleen, which is destined to re- 

 ceive the impurities that would prevent it from duly performing its functions. 



After this singular system of physiology comes what might be called the zoo- 

 logical part of the treatise. Timaeus tries to discover the cause of the diversity 

 of the forms of animals, and exposes the system of the Pythagoreans respecting 

 the Metempsychosis. At the first transformation, the unsteady and unjust men 

 are changed into women ; at the second they are metamorphosed into animals ; 

 and, according to their degree of culpability, become birds or quadrupeds. The 

 most wicked, those who are no longer worthy of breathing air, are transformed 

 into fishes. By means of successive transformations, Timaeus explains the simi- 

 larity that is observed among the animals of the different classes. This resem- 

 blance does not come merely from the circumstance that all have a like soul, but 

 from the circumstance that each of them retains in its present state something of 

 its previous state. 



The soul of plants (and it must be remembered that, in its general accepta- 

 tion, the word means nothing more than an internal principle of motion) presides 

 over their preservation, their growth, and their re-production. Besides this vege- 

 tative soul, animals have the sensitive or passionate soul, — ^man alone has a rea- 

 sonable soul. 



We thus find very distinctly expressed in the Timaeus these three principles of 

 motion, which correspond to what have since been named organic life, animal 

 life, and intellectual life. Yet we have not here science properly so called, or at 

 least it is a priori science, and such as might be expected of a system of meta- 

 physics like Plato's. In fact, if human knowledge consists of reminiscences, it 

 is by separating himself from the world that man may expect to recover it ; and in 

 the search of truth he ought to engage in reflection and not in observation. It 

 will easily be conceived with such a mode of proceeding, the Platonic school 

 could not render much service to the natural sciences. It may even be said that 

 it retarded them, by opposing in some degree the propagation of the doctrines of 

 Aristotle. 



In the Timaeus, Plato exposes his own doctrine, which is easily recognized by 

 the form of the dialogue. Thus the words which he places in the mouths of the 

 different interlocutors are to be considered as the true expression of his sentiments^ 

 excepting in some parts, which are evidently allegorical. 



The fictions which occur in the different treatises of that philosopher, are in 

 part owing to the poetical turn of his mind, and in part to the necessity of veiling 

 certain doctrines which it would have been dangerous for him to expose more 

 clearly. Notwithstanding this precaution, Plato was accused of impiety, as Anax- 

 agoras and Socrates had been before him ; but he fared better than they, and 

 continued to teach at Athens to an advanced age. He died at the age of eighty, 

 one, in the year 348 before Christ. 



Aristotle, a disciple of Plato, was his successor in philosophy. Before entering 

 upon the history of that great man, who formed so remarkable an epoch in science, 

 it will be proper to advert to some of his predecessors, of whom we have not yet 

 spoken. Some of them belong to no particular sect of philosophy ; others are of 

 the school of the Asclepiadffi, which, as we have said, cultivated science only with 

 reference to practical utility. Of the former Herodotus and Zenophon ought to 

 be particularly noticed. 



Herodotus, the oldst prose writer whose works have come down to us, was bom 

 at Halicamassus in Caria, about the year 484 before Christ. He was a great 

 traveller, having visited successively a part of the East, Egypt, and Greece ; 



