96 BIOLOGY AND PHYSICAL SCIENCES 



them to the chemical elements as they 

 appeared to science before the discovery of 

 the periodic law and the breaking down and 

 probable building up of elements. Hegel 

 pointed out that not only was Kant's list 

 of categories incomplete, but that the cate 

 gories bear a natural relation to one another, 

 the lower being the more abstract or empty 

 general conceptions furthest from reality, and 

 the higher being the more concrete and 

 definite ones nearest to reality. If, for in 

 stance, we regarded our experience as con 

 sisting of nothing but qualitatively different 

 data we should be using an empty and 

 abstract category. If we regarded it as a 

 world of substances acting on one another 

 we should be seeing it under a much less 

 empty category, and the qualities and their 

 chan 6 es would now appear as the qualities 

 and changes of substances. If we regarded 

 it as a world of living organisms we should 

 be using a still higher and less empty 

 category ; for substance, quality, and activity 

 would now be united in a conception out 

 of which they all issue, the activity being 

 no longer regarded as an accident of the 



