Address to the British Association 225 



necessarily be, as to its details, a science of the future. For 

 just as Physiology requires as a necessary antecedent condi- 

 tion a knowledge of anatomy — since we must know that 

 organs exist before we investigate what they do — so Psychology 

 requires as a necessary antecedent condition an already ad- 

 vanced physiology. It requires it because we must be 

 acquainted with the various functions before we can study 

 their synthesis and interactions. 



When, however, this study has advanced, one most im- 

 portant result of that advance will be a knowledge, more or 

 less complete, of the innate powers of organisms, and there- 

 fore of their laws of variation. By the acquisition of such 

 knowledge we shall be placed in a position whence we may 

 advance, with some prospect of success, to investigate the 

 problem of the ' Origin of Species ' — the biological problem 

 of our century. 



This reflection leads me back once more to my starting- 

 point, the merits of the great French naturalist of the last 

 century, whose views as to variation, and as to animal 

 psychosis, have enabled me to bring before you the questions 

 on which I have presumed to enter. BuflPon's claims on our 

 esteem have, I think, been too much forgotten, and I rejoice 

 in this opportunity of paying my debt of gratitude to him by 

 recalling them to recollection. As to the questions which 

 his words have suggested to me and upon which I have thus 

 most imperfectly touched, the considerations I have ventured 

 to offer may or may not commend themselves to your 

 approval; but, at least, they are the result of not a few 

 years of study and reflection, and I am persuaded they have 

 consequences directly or indirectly affecting the whole field of 

 biological inquiry, which belief has alone induced me to 

 make so large a call upon your patience and your indulgent 

 kindness. 



VOL. II. P 



