THE UNIQUENESS OF LIFE 145 



(&) Secondly, there is a sense in which all biologists may 

 be called vitalists, inasmuch as no one can pretend that the 

 mechanical re-description of vital phenomena has as yet gone 

 very far. Professor Bateson writes: " If those who proclaim 

 a vitalistic faith intend thereby to affirm that in the processes 

 by which growth and division are effected in the body, a part 

 is played by an orderly force which we cannot now translate 

 into terms of any known mechanics, what observant man is 

 not avitalist?" (1913, p. 80). 



We must distinguish between a negative and a positive 

 vitalism. When we assert that no vital activity in its ob- 

 served totality has ever been completely described in mechan- 

 ical terms, as one might describe the movement of a glacier 

 or the spread of a conflagration, we are making a scientific 

 statement which we believe to be accurate at the present 

 time (1919). That it will hold true a hundred or a thou- 

 sand years hence does not follow from the evidence sub- 

 mitted, for we do not know what changes are still to be 

 made in the concepts of chemistry and physics, or what dis- 

 coveries will reward inquiry into, for instance, the physiology 

 of correlation. It may be that a mechanistic formulation 

 of the essential activities of organisms is quite impossible, 

 but that could not be legitimately inferred from the argu- 

 ments we used. These went to show that the description 

 of vital occurrences in terms of present-day chemistry and 

 physics does not adequately express the connection of the 

 sequences, still less their correlation. We can speak only 

 about the chemistry and physics that we know. Sufficient 

 unto the day is the mechanism thereof. The formula of chem- 

 istry and physics prove inadequate, and in part irrelevant. 

 If we go on to say that they are inadequate because the 

 organism has a monopoly of a peculiar kind of energy, or 



