Nov. 1898.] BOTANICAL SOCIETY OF EDINBUKGII 129 



They have noticed that energy had much to do with brain 

 fibres, and they have fancied that it was the sole ruler ; 

 whereas it only holds a divided sway. This is the modern 

 theory of vitalism, which we owe implicitly, though not 

 explicitly, to the teaching of Pasteur. It amounts to this : 

 God has created two types of force in His universe — 



1. Energy, which is always acting, always a constant, 

 and which has as its vehicle all matter optically active or 

 inactive. 



2. Life, which can only act under certain peculiar con- 

 ditions, and which has as its vehicle optically active matter. 

 Constancy, and the absence of limitation, are the character- 

 istics of energy. Inconstancy, and limitation, are the 

 characteristics of life: 



To explain Xature, we would thus have four independent 

 concepts : Matter, Ether, Energy, and Life. 



I may be told all this is mere speculation, and be asked 

 to furnish facts. But we cannot argue about facts, that is 

 to say, about our sensations. We must accept them, and 

 what science has to do, is to try to arrange, and classify 

 them. Science discusses our concepts, whether they make 

 our sensations more intelligible or less. 



I claim for vitalism, that it makes some of our sensations 

 more intelligible, than they were a year or two ago, when 

 almost all scientists believed that the brain originated 

 nothing, and that thoughts were a response to environment. 

 In the words of Sir John Batty Tuke, spoken on the 29th 

 July 1898, "All impulses come from without, a fact which 

 must have important bearings on the question of the 

 adjustment of outer to inner relations." When I heard 

 this sentence at the meeting of the British Medical 

 Congress, it appeared to me not to be a fact ; and after 

 thinking the matter over, I venture to propound the 

 opposite statement, that most impulses come from within, 

 from the brain of the person himself, or of some other 

 human being, and that only comparatively few, come from 

 without, from inorganic nature — the sun, moon, earth, 

 sea, etc. 



On no other hypothesis can I understand what appears 

 to me a fact — the great difference which exists between 

 organic and inoraanic nature. 



