PRESENT PROBLEMS OF PHYSIOLOGY 431 



little; we may call it soul, animal spirits, vital principle or force, 

 ether, nervous fluid, inner sense, consciousness or psyche, but plus 

 c'est change, plus c'est la meme chose. We may differ as to whether 

 this something is connected with living matter in all its forms or 

 whether its manifestations are limited to the nervous tissues, but 

 if we admit its existence as a causal factor in any of the phenomena 

 of life, then it seems to me that we adopt the standpoint of vitalism, 

 and the nature of our work as well as our theories will be influenced 

 thereby. The standpoint of the mechanist is simple. He believes 

 that all the properties of living matter are of a chemico-physical 

 nature, that is, properties that are dependent upon the structure 

 and arrangement of the molecules and the eternal characteristics 

 of their constituent parts. The C, H, 0, N, S, P, etc., that enter into 

 its composition carry with them their individual properties, and if 

 nothing else is present in living matter, the phenomena exhibited 

 by it must be a resultant of these properties, as the phenomena 

 exhibited by sodium chloride depend upon the combination of the 

 properties of the constituent sodium and chlorine. From this stand- 

 point we may assume that if there is in living matter any recog- 

 nizable form of energy not hitherto classified, it is intrinsically pre- 

 sent in dead matter also, and we may hope to discover its existence 

 by purely physico-chemical methods of investigation, with the 

 probability, indeed, that it will be recognized first by the chemist or 

 the physicist with his more exact methods and more favorable 

 conditions for quantitative analysis. If we are unwilling to adopt 

 this standpoint, then it seems to me that, unless we deem it wiser 

 to assume an entirely agnostic attitude, we are logically forced to 

 take one of two positions. With the older physiologists we may 

 boldly assume the existence in living organisms of a finer stuff inter- 

 mingled with the so-called matter, a substance that is not matter 

 as we understand that term in science, but which, in combination 

 with matter, gives to living things their distinctive characteristics; 

 or we may assume the existence in the universe of a reality other 

 than matter, with the belief that it is influenced by and exerts an 

 influence upon matter only in the living form, in some such way 

 as the earlier physicists postulated an ether that can be affected by 

 matter only when in a certain state of vibration. If I read them 

 correctly, most modern scientific authorities adopt substantially 

 this latter point of view. The so-called psychical phenomena of life 

 are differentiated from the physical, but at the same time it is 

 admitted that the subjective or psychical manifestations are depend- 

 ent upon physico-chemical changes in the material substratum. 

 Huxley states the matter with his usual candor and clearness : 

 "It seems to me pretty plain that there is a third thing in the uni- 

 verse, to wit, consciousness, which in the hardness of my head or 



