December i6, 1920] 



NATURE 



495 



suggested in regard to the human soul, like a 

 wise prince among his subjects, or a good 

 father in his household, by directing, suspending, 

 and releasing activities rather than by exerting 

 them. 



Now, after this strong and tough fare purveyed 

 by Driesch, Prof. Thomson's book may almost 

 be called "light reading"; clearly it could not 

 have been written from an easy chair, but it can 

 easily be read in such. The aim of a study of 

 xmimate Nature, Prof. Thomson tells us, "is to 

 state the general results of biological inquiry 

 which must be taken account of if we are to think 

 of organic Nature as a whole in relation to the 

 rest of our experience," and it is just such a survey 

 that he presents to us in a most agreeable manner. 

 There is no inclination to make, or adopt, a 

 system, and the criticism is seldom very penetrat- 

 ing. One is told what is meant, in contemporary 

 literature, by the ideas of "Body and Mind," 

 "Organism and Mechanism," " Adaptiveness and 

 Purposiveness," "Disharmonies and Shadows" 

 that prevent us from seeing, in the organic world, 

 "the True, the Beautiful, and the Good," and so 

 on. But, in the main, the discussion centres 

 round the contrasted hypotheses of mechanism and 

 vitalism. 



What is vitalism? There are at least three 

 grades, the author says. First there is a recogni- 

 tion that the physico-chemical processes that go 

 on in inorganic materials cannot explain animal 

 Ijehaviour ; knowing only the former, we cannot 

 predict the latter. This is the "very thin edge 

 of vitalism." Next there is the view that some 

 particular "vital force," or mode of energy, 

 operates in living substance, but not elsewhere, 

 l-astly, it has been thought that the organism is 

 the scat of a non-energetic factor, or entelechy. 

 This is "thorough-going vitalism." In addition 

 to these hypotheses there is Mr. E. S. Russell's 

 "methodological vitalism" — a biological fact, such 

 as a migration, is a unique activity which has 

 to be explained. It is not explained by decom- 

 posing it into an infinity of physico-chemical re- 

 actions, for then the fact itself disappears, and 

 we are left only with a great number of little, 

 partial views or aspects of it, which are, no doubt, 

 expressions of a mechanism of matter and energy, 

 but not the thing itself. VVe must, therefore, 

 study animal behaviour, not as a series of energy- 

 transformations or even as the result of the 

 operation of mind, but as irreducible data to be 

 dealt with by themselves. This Prof. Thomson 

 regards as the most satisfactory attitude yet sug- 

 gested, and there can be little doubt about that; 

 it is a method rather than an "ism," and its out- 

 come is investigation. 



NO. 2668, VOL. 106] 



What is mechanism? .'\s usually understood, 

 the mechanistic conception of life states that the 

 activities of organisms are physico-chemical 

 — and nothing else. The notion comes down to 

 us from Descartes, who recognised nothing in the 

 organic world but matter and its configurations 

 and motions (for, even when he placed the " sensi- 

 tive soul " in man, he did not regard that as 

 essential to animality). Now, matter, when our 

 hypothesis of mechanism was elaborated, meant 

 the chemical atoms ; its configurations were 

 chemical compounds, and its motions the 

 expressions of energy-transformations. How to 

 deal with consciousness on this hypothesis was 

 always dillicult, but, as a rule, the thorough- 

 going mechanist ignored the condition, and re- 

 garded as " realities " only objective things and 

 processes. This was called "monistic panhylism " 

 — which sounds well, at all events. 



Whichever of these attitudes one takes up (for a 

 biologist is expected to be either a mechanist or 

 a vitalistjdejjends on one's education and its media, 

 and also upon one's temperament. Thus Prof. 

 Thomson " confesses to some sympathy with those 

 who ask why there should be all this straining and 

 striving to remove organisms from the domain 

 which includes the stars and precious stones, 

 Northern Lights and dewdrops " ; but he does not 

 think that mechanism "exhausts the reality of the 

 earth and the heavens, still less that of the flower 

 in the crannied wall." On the other hand. Prof. 

 D'Arcy Thompson is "not ashamed to uphold" 

 that "the earth itself and the sea, the earth with 

 its slowly changing face and the sea multitudinous 

 with all its tides and currents and great and little 

 waves, constitute a mechanism ; the heavens them- 

 selves, the sun and moon and all the little stars, 

 are a glorious mechanism." Obviously, having to 

 make the choice induces sentiment. Now it would 

 not be rash to say that the difference between 

 mechanism and vitalism may suggest that between 

 the Homoousians and the Homoiousians, but, like 

 Gibbon when he wrote about the Arian contro- 

 versies, one fails to trace any "real and sensible 

 distinction" between the "isms" that concern us 

 here. What does one find if he tries to think it 

 all out in the light of strictly modern, physical 

 speculation? Does "determinism" mean anything 

 at all in science? It is "strict " only when we deal 

 with mathematical functionality, and even then 

 is not that just because the human mind, having 

 made the rules, experts the answer? Obviously, 

 this " ism " is a method, and not a result. Then, 

 again, it is still very convenient to speak about 

 atoms, etc. ; but in pure speculation (which is our 

 field just now) we must get down to bedrock con- 

 ceptions. Then the ultimate data of science are 



