NATURE 



[September 2, 191 



their effort to the legitimate function of science — 

 the discovery of natural phenomena and their classi- 

 fication into general laws by logical mathematical 

 processes? " (p. 31). 



The account of the growth of the mechanistic 

 view in science and of atomism, and the criticism 

 of them and development of a science of energetics 

 by Rankine, Mach, Duhem, and Ostwald, are fairly 

 adequate, and direct attention to some points — 

 notably in Rankine 's attitude — which have been 

 forgotten by most people. It is rather disappoint- 

 ing to find no mention of Stallo's extremely 

 important work in the theory of knowledge, 

 especially when we see that the second chapter 

 is headed "The Metaphysical Tendencies of 

 Modern Physics," and read such passages as that 

 .on p. 70. But Prof. More's problem is not quite 

 the same as Stallo's. In Stallo's time physicists 

 vigorously denied that their theories had a meta- 

 physical basis, and it was Stallo's purpose to 

 show that the physicists were mistaken in their 

 denial. But at the present time such a theory as 

 Larmor's has an avowedly philosophical back- 

 ground. The great obligation of modern physics 

 to Descartes is seen from the admirable discussion 

 of Descartes' physical system in chapter iii. "A 

 comparison of his [Descartes'] postulates and 

 conclusions with those of our modern theory shows 

 them to be almost identical, if we change his 

 antiquated knowledge and his discarded meta- 

 physical language into modern terminology " (p. 

 67; cf. pp. 98, lOl). 



The fourth chapter is a reprint of an article in 

 the Philosophical Magazine, and, under the head- 

 ing "The Scientific Method," contains a very 

 sensible critical review of recent physical theory. 

 Prof. More himself advances a hypothesis to make 

 the ratio ejni agree with the experimental evi- 

 dence (p. 140). The fifth chapter is on "The 

 Classical'and the New Mechanics," and here Prof. 

 More concludes that, if we finally adopt the most 

 modern thesis that matter is the manifestation of 

 energy, we are acknowledging that " the guides to 

 knowledge are now to be found in those subjective 

 impressions which must depend on the individual, 

 and vary with him. . . . The classical natural 

 philosophy of Newton and Galileo has drifted into 

 that transcendental symbolism which is apt to take 

 place when German thinkers become the leaders in 

 philosophy" (p. 163). The sixth chapter is on 

 "Skepticism and Idolatry in Science," and here 

 some of the writings of Poincar^ and Sir Oliver 

 Lodge make admirable illustrations; and the 

 seventh chapter is on "Science as the Arbiter of 

 Ethics." This is a thoughtful book, and though 

 easy to read, is not superficial. 



(2) Mr. Redgrove's book makes a great point 

 NO. 2392, VOL. 0.61 



of the fact that experience is' subjective, as 

 Berkeley pointed out, and of which Mach has made 

 such illuminating use in physics. Of course 

 materialism becomes easily refutable from this 

 point of view. Mr, Redgrove leans to the 

 mysticism of John Smith the "Cambridge 

 Platonist," Boehme, and Swedenborg, but — and 

 this would surprise some after that — he adopts 

 what seems to be a very sensible attitude in his 

 emphasis on the validity of the laws of nature, and 

 the fallacy of " Christian Science " metaphysics. 

 Mr, Redgrove follows Mill in thinking that mathe- 

 matical truth is merely founded on experience, and 

 holds that absolute truth is unknown and unknow- 

 able. In spite of this we may approach truth, 

 "just as a mathematical series may for ever pro- 

 gress towards some limit which it never reaches " 

 (p. 86). The mathematical illustrations seem to 

 be quite irrelevant : we might just as well illustrate 

 a fanciful doctrine that we can attain the limits of 

 knowledge over and over again in our lives, and 

 yet approach no definite knowledge, by instancing 

 the function sin x as x proceeds to infinity along 

 the real axis. ^. 



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