58 THE NEW PHYSIOLOGY. 



Professor Macallum of Toronto, in a very able and 

 interesting presidential address to the American Society 

 of Biological Chemistry two years ago. 1 After frankly 

 admitting that the apparent difficulties of the mechanistic 

 interpretation of life " put a task upon the human 

 spirit which is apparently not imposed thereon in the 

 theoretic explanation of any other department of 

 science," he proceeds to argue that this is because 

 " our knowledge of the laws that operate in matter is 

 as yet only a very remote approximation to the whole 

 of the lore on this subject that is possibly attainable and 

 that will be ultimately attained." He feels, however, 

 that this defence of the mechanistic theory is somewhat 

 dangerous, and therefore proceeds to point out " that 

 though we know so little of the properties and laws of 

 matter, we know it with a degree of certainty which is 

 not exemplified in the case of any other department of 

 the known or the knowable, and further that the most 

 rational method of interpreting vital phenomena is to 

 explain the unknown in terms of the known, to trace 

 back the causation of the obscure and mysterious to the 

 operations of wholly natural laws and processes." 



Now with this latter sentiment I am in entire agree- 

 ment ; but I would point out that Professor Macallum 

 had just invoked, not what he considers the known, but, 

 on the contrary, the totally unknown properties of 

 matter, to furnish us with a future physico-chemical 

 explanation of life. I confess that there is in his argu- 

 ment a certain theological smack which strongly appeals 

 to me as a fellow-Scotchman. In the domain of 

 " apologetics " he would, I feel sure, make a great 

 1 Journal of Biological Chemistry, xvii. p. viii, 1914. 



