32 The Unity of the Organism 



— is not, merely on the ground of what is learned by later 

 study about the differences in makeup of the two, is literal 

 nonsense. It is a virtual denial of the validity of oberva- 

 tional knowledge. Granted that science can not rest satis- 

 fied with "common-sense" knowledge, there is still no ground 

 for repudiating all commonsense. 



Attempting to ascertain what the trouble is with biolo- 

 gists who reason thus about individuality, one soon dis- 

 covers that the botanist who deals with a tree thus unjustly 

 quite ignores the obvious and unescapable fact that the raw 

 material of all his botanical knowledge is individual plants 

 taken one after another; that for trees there is an each tree; 

 that each, as it actually stands before him, is one, not two 

 or three or any other number ; and that it is not in the least 

 confusable witli any other tree, no matter if several are 

 connected together by their roots or in some other way. 

 These confused-minded persons either ignore the patent facts 

 of observation., or if their sophistication is refined, they deny 

 the validity of the "mere perception" of an individual when 

 that way of predicating individuality is measured against 

 supposedly more fundamental principles of scientific knowl- 

 edge-getting, as analysis is held to be. 



This question of more and less fundamental principles 

 of scientific procedure, especially those involved in analysis, 

 is undoubtedly of great importance. But undoubtedly, too, 

 it is a question of the nature of scientific knowledge rather 

 than of the nature of plants and animals, so does not fall 

 within the scope of such a treatise as the one now occupying 

 us. The question before us is that of the nature of the in- 

 dividual organism. 



As soon as we see the necessity of separating these two 

 questions, and address ourselves to the strictly objective 

 question, we perceive that the difficulties center around the 

 fact that no individual plant or animal is simple in its con- 

 stitution, but in alniost all cases is exceedingly complex, 



