AND THEIE FUNCTIONS. 187 



of cephalopods, crustaceans, and his Entoma, and he evidently 

 suspected the existence of visual organs in solens and pectens. 



Kespecting the sense organs in general, it may be said 

 that there are many passages difficult to understand, and 

 sometimes inconsistent, in Aristotle's v^orks. A discussion 

 of one series of such passages will conclude this chapter. 



He says that philosophers of his time tried to assign to 

 each sense organ one, and only one, of the elements, but that, 

 since there are five senses they found some difficulty in 

 assigning the four elements to them.* He does not seem 

 to adopt this view of the sense organs, but in many passages 

 of his works he attempts to assign one or more of the sense 

 organs to certain elements. In De Sensu, &c., c. 2, 4386, 

 e.g., he assigns vision to ivater, hearing to air, and smell to 

 fire, and, in De Anima, iii. c. 1, 425a., he assigns vision and 

 hearing to water and air, respectively, smell to either, and 

 suggests that all the senses may be assigned to fire, and 

 touch to earth. The chief sensory organ of touch being, 

 according to Aristotle, the heart or region of the heart, 

 which is the centre of heat, this attempt, in De Anima, 

 iii. c. 1, 425a, to assign the senses to the elements is difficult 

 to understand. Some commentators consider the passage 

 cited above from the De Anima to be corrupt. 



* De Sensu, rfc, c. 2, 437rt. 



