592 



SCIENCE. 



[N. S. Vol. XX. No. 514. 



of metaphysics. But the metaphysics will 

 naturally be realistic rather, than idealistic. 



III. 



Just as logical processes may be regarded 

 as, at the same time, psychological pro- 

 cesses, so they may be regarded, with equal 

 right, as vital processes, coming thus under 

 the categories of evolution. The tendency 

 so to regard them is very marked at the 

 present day, especially in France and in 

 this country. In France, the movement 

 has, perhaps received the clearer definition. 

 In America the union of logic and biology 

 is complicated— and at times even lost sight 

 of — by emphasis on the idea of evolution 

 generally. It is not my intention to trace 

 the history of this movement, but I should 

 like to call attention to its historic motive 

 in order to get it in a clear light. 



That the theory of evolution, even Dar- 

 winism itself, has radically transformed 

 our historical, scientific and philosophical 

 methods, is quite evident. Add to this the 

 influence of the Hegelian philosophy, with 

 its own doctrine of development, and one 

 finds the causes of the rather striking 

 unanimity which is discoverable in many 

 ways between Hegelian idealists, on the one 

 hand, and philosophers of evolution of 

 Spencer's type, on the other. Although two 

 men would, perhaps, not appear more 

 radically different at first sight than Hegel 

 and Spencer, I am inclined to believe that 

 we shall come to recognize more and more 

 in them an identity of philosophical concep- 

 tion. The pragmatism of the day is a 

 striking confirmation of this opinion, for it 

 is often the expression of Hegelian ideas 

 in Darwinian and Spencerian terminology. 

 The claims of idealism and of evolutionary 

 science and philosophy have thus sought 

 reconciliation. Logic has been, naturally, 

 the last of the sciences to yield to evolu- 

 tionary and genetic treatment. It could 

 not escape long, especially when the idea 



of evolution had been so successful in its 

 handling of ethics. If morality can be 

 brought under the categories of evolution, 

 why not thinking also? In answer to that 

 question we have the theory that thinking 

 is an adaptation, judgment is instrumental. 

 But I would not leave the impression that 

 this is true of pragmatism alone or that it 

 has been developed only through pragmatic 

 tendencies. It is naturally the result also 

 of the extension of biological philosophy. 

 In the biological conception of logic, we 

 have, then, an interesting coincidence in 

 the results of tendencies differing widely in 

 their genesis. 



It would be hazardous to deny, without 

 any qualifications, the importance of genetic 

 considerations. Indeed, the fact that evolu- 

 tion in the hands of a thinker like Huxley, 

 for instance, should make consciousness and 

 thinking apparently useless epiphenomena 

 in a developing world, has seemed like a 

 most contradictory evolutionary philosophy. 

 It was difficult to make consciousness a real 

 function in development so long as it was 

 regarded as only cognitive in character. 

 Evolutionary philosophy, coupled with 

 physics, had built up a sort of closed system 

 with which consciousness could not inter- 

 fere, but which it could know, and know 

 with all the assurance of a traditional logic. 

 If, however, we were to be consistent evolu- 

 tionists, we could not abide by such a re- 

 markable result. The whole process of 

 thinking must be brought within evolution, 

 so that knowledge, even the knowledge of 

 the evolutionary hypothesis itself, must 

 appear as an instance of adaptation. In 

 order to do this, however, consciousness 

 must not be conceived as only cognitive. 

 Judgment, the core of logical processes, 

 must be regarded as an instrument and as 

 a mode of adaptation. 



The desire for completeness and con- 

 sistency in an evolutionary philosophy is 

 not the only thing which makes the denial 



