president's address. 17 



general contention here supported might be summarised thus : — 

 Living activity can only be known to scientific investigation as 

 manifested in changes in configuration and motion of certain 

 bodies in space and time. Such a body is for science, therefore, 

 a material system, and, as such, its function or change of motion 

 or configuration implies material structural constitution, i.e., a 

 mechanism embodying and determining the functional change. 

 A dissociation of function and structure — a divorce between 

 mechanism and motion, living or other — is an impossibility for 

 scientific thought. 



That another interpretation of organism transcending that of 

 mechanism, is not only possible but necessary for the human 

 intelligence, I have freely admitted. For such a view it may be 

 necessary to hold that as regards its organisation an organism is 

 no mere object in space; in other words, that it is not " a purely 

 material system." Nevertheless, it is only as an object in space 

 that it can become for us an object of scientific investigation — as 

 part of a material system exhibiting configuration and motion. 

 It is with the changes in motion and configuration manifested by 

 living objects in space that biology, both on its morphological and 

 physiological sides, as a scientific discipline, has to do. And if, 

 as I firmly believe, the conception of organism as a material 

 system is inadequate to express the full concrete reality which 

 organisation possesses for thought; this imperfection is to be 

 remedied, not by the intercalation of the teleological conception 

 at a supposed break in the continuity of possible mechanical 

 interpretation — a break which represents merely the present 

 limit of structural observation— but by a complete philosophical 

 re-interpretation — a philosophical reconstruction — of biological 

 fact, in the light of its significance for the general theory of 

 knowledge. 



I feel sure that Dr. Haldane would emphatically demur to my 

 describing his proposition as one which aims at the intrusion of 

 one category of explanation into the sphere of operation of a 

 radically different one. But his assertion of a failure on the part 

 of the mechanical principle to explain the elementary phenomena 



