FRANCIS WILLUGHBY. 35 



in order to meet what is called by Cicero " the 

 insatiable variety of nature ; " that it can exhibit 

 only disjointed parts of the universal frame of 

 being. On the whole, an artificial system is best 

 adapted for use, while anatural system alone can 

 enable us to know the probable station of any 

 creature in the system of the scale of being, by 

 the affinities it possesses to others, and the ana- 

 logies by which it is related and represented. 

 The attainment of the best natural system is, 

 however, likely to follow from the inquiries made 

 by the best artificial systems. 



The first formation of an artificial system, 

 when all circumstances are considered, will ever 

 be regarded as an interesting epoch in the annals 

 of science. It is now intended to contemplate 

 that event as it is presented m the history of 

 Aristotle. Scarcely any thing is known with 

 certainty of the early life of this illustrious man, 

 except that he studied at Athens with the most 

 intense assiduity under Plato, and that this 

 eminent philosopher used to call him " the mind 

 of his school ;" and when Aristotle was not there, 

 to say, "The soul of the school is absent." 



Some time after the death of Plato, which 

 happened about the year 348 B.C. and when 

 Aristotle was thirty-six years old, he began to 

 teach publicly at Athens ; and after having gained 

 the highest celebrity as an instructor of youth, 

 he was- invited by Philip, king of Macedon, to 

 undertake the education of his son Alexander 

 then, about fifteen years of age. The letter. ia 



