Aristotle 51 



as the Epidemics and the Aphorisms which exhibit an investi- 

 gator intent on recording actual observations and on deducing 

 general laws therefrom. Had the Hippocratic method been 

 extended by Aristotle beyond the field of natural history, where 

 he freely follows it, to that of physiology, the succeeding 

 generations might have established medicine far more firmly 

 as a science. 



An important factor in Aristotle's physical and physiological 

 teaching is the doctrine that matter is continuous and not made 

 up of indivisible parts. He thus rejected the atomic views of 

 his predecessors Leucippus and Democritus which have been 

 preserved for us by the poem of Lucretius. The different kinds 

 of matter existing merely in their state of simple mixture 

 formed various uniform or homogeneous substances, homoeomeria, 

 of which th&tissues of living bodies provided one type. We now 

 consider tissues as having structure made up of living cells or 

 their products, but to Aristotle their structure was an essential 

 fact following on their particular elemental constitution. The 

 structure of muscle or flesh was perhaps comparable to that 

 of a crystalline substance, for, as we have seen, Aristotle made 

 no fundamental distinction between organic and inorganic 

 substances , which are in his view alike subject to the processes 

 of generation and corruption. The difference between them 

 lies not in their structure but in their potential relation to the 

 various degrees of soul, the vegetative, the animal, and the 

 rational. 



' There are ', says Aristotle, ' three degrees of composition, 

 and of these the first in order is composition out of what some 

 call the elements, earth, air, water, and fire. . . . 



The second degree of composition is that by which the 

 homogeneous parts of animals (o/ioiojue/)?j), such as bone, flesh, 

 and the like, are constituted out of [these] primary sub- 

 stances. 



The third and last stage is the composition which forms the 



D 2 



