KANT AND BIOLOGY 75 



Kant enumerated definitely the * categories ' 

 or general ideas under which he believed that 

 our perceptions are ordered. This list seems 

 very artificial, and is based on the old formal 

 logic, but it includes the ideas of substance, 

 cause and effect, and reciprocal action the 

 ideas of the physics of Kant's time. He him 

 self, it may be remarked, was a physicist and 

 mathematician of no mean repute. The list 

 limits perception to the perception of a purely 

 physical world, such as the physical sciences 

 described, and he had no special category 

 for living organisms. On Kantian principles, 

 therefore, a living organism can only be per 

 ceived as a material structure or mechanism. 

 In this respect, Kant was at one with the 

 mechanistic school of biologists. For him, 

 however, the reason why we must perceive 

 organisms as mechanisms is not because they, 

 in themselves, are mechanisms, but because 

 the mind is so constituted that it can only 

 perceive them as mechanisms. 



Kant's successor, Hegel, pointed out that 

 his list of categories was incomplete in 

 various directions: also that a special cate 

 gory or categories ought to be added 



