THE DOGMA OF EVOLUTION 



tions of life which are clearly mechanical and who 

 does not twist those laws into a pseudo-biological 

 mechanics in which the words are the words of me- 

 chanics but the laws are not mechanical. This un- 

 usual credit can be given to Professor D' Arcy Thomp- 

 son who, in his recent work, Growth and For?n, has 

 worked out many ingenious problems of organisms 

 which are true physical problems; who says frankly 

 that zoologists have scarce begun to dream of defin- 

 ing, in mathematical language, even the simpler or- 

 ganic forms. Unlike Professor Osborn, he does not 

 say, force and energy, when he means something en- 

 tirely different, and yet he does show that many ac- 

 tions of organisms are due to mechanical forces which 

 the most advanced mechanistic materialists are still 

 "fain to refer to vital instinct or design rather than 

 to the operation of physical forces." Professor Thomp- 

 son has the rare quality, also, of knowing philosophy 

 as well as zoology, and he has looked outside his nar- 

 row laboratory into the wide field of human know- 

 ledge; he finds that while zoologists can profitably 

 apply the laws of physics to many problems of life 

 which they have neglected to consider, yet their 

 sweeping assumption that all the functions of life 

 are physical is not in accordance with the facts, for 

 "it is plain that we have no clear rule or guide as to 

 what is 'vital' and what is not." 



I am quite willing to rest my argument on the con- 

 clusions of Professor Thompson. I am convinced that 



C 238 ] 



