October 20, 1923] 



NATURE 



567 



The Scope of Science. 



The Domain , oj Natural Science : the Gifford Lectures 

 delivered in the University of Aberdeen in 1921 and 

 1922. By Prof. E. W. Hobson. Pp. xvi + 510. 

 (Cambridge : At the University Press, 1923.) 

 21s. net. 



DR. HOBSON'S important book falls into three 

 main divisions : the first consists of four lectures 

 and describes his general philosophical position, or 

 rather, as he would prefer us to say, his view of the 

 nature of science and its relation to philosophy ; the 

 second, being in fact the bulk of the book, comprises 

 fourteen chapters, giving a survey of the development 

 of scientific thought in all its main branches from 

 mathematics to biology ; the third, which is a sort of 

 epilogue, brings the book within the terms of the 

 Gifford Trust and deals with the limits of natural 

 science and religion : this is the last two chapters. 

 We will say a few words about each in turn. 



Dr. Hobson's general view of the nature of science 

 agrees with that of Mach and Karl Pearson. He 

 explains it carefully and frequently, and arranges the 

 main substance of the lectures so that they depend on 

 this thesis and illustrate it. In this view a scientific 

 theory is "a conceptual scheme, designed by the 

 synthetic activity of the mind, working with the data 

 of perception, for the purpose of representing particular 

 classes of sequences and regularities in our percepts." 

 It has nothing to say as to the reality, or non-reality, 

 of anything behind phenomena, nothing as to efficient 

 or final causes. It is an intellectual shorthand, enabling 

 mankind to deal more and more economically and 

 effectively with the facts of perception which crowd 

 in upon us. 



Dr. Hobson is very careful to remind us of the 

 implications of this point of view at every turn in his 

 argument, and it is especially congenial to his own 

 mathematical mind. For this reason he has been able 

 to give us an exposition of the doctrine, quite un- 

 exampled in England, if not abroad. Mathematics 

 obviously illustrate the thesis best, and he shows us, 

 e.g., how in dynamics the failure sharply to distinguish 

 the conceptual statement of scientific laws and theories 

 from statements as to percepts has obscured the true 

 nature of science. We can speak and think clearly 

 about a conceptual body moving in conceptual space 

 according to definite numerical specifications, whereas 

 there is no meaning in the assertion that a body moves 

 uniformly in a straight line in physical space. In the 

 same way Dr. Hobson quite rightly treats Einstein's 

 theory of relativity as a conceptual correction of the 

 Newtonian conception : not as a revolution and, above 

 all, not as a new philosophy. 



NO. 2816, VOL. 112] 



It was certainly a happy thought on the part of the 

 lecturer to turn his general argument into a sort of 

 generalised history of science, and a happy liberality 

 on the part of the Gifford Trustees which enabled them 

 to include it within the corners of their scheme. 

 Histories of science are much in the air just now, and 

 we are constantly seeing small popular books issued 

 on some aspect of the subject, generally biographical. 

 Here we have a survey by a master of the fundamental 

 science of all, who has for years interested himself in 

 general scientific development, and applies an acute, 

 impartial and cautious mind to a statement and an 

 estimate of all the leading theories, especially the more 

 recent, in physics, cosmology and biology. It is a 

 most careful and substantial work which will be of the 

 greatest service to future toilers in the same field. 

 For between the popular histories and the specialist 

 and the philosophical— of which this is an eminent 

 example — there is still a gap waiting to 'be filled by a 

 concrete, lively, up-to-date survey, such as Mrs. Fisher 

 attempted in the 'seventies and 'eighties. 



Dr. Ilobson's survey requires careful reading, as it 

 has arisen from careful and thorough thinking and 

 writing. He passes from weighing and delimiting the 

 determinist physical schemes of science to a similar 

 comparison and estimate of dynamical theories. From 

 this to a discussion of the conservation of matter and 

 energy, a sphere which gives him scope for penetrating 

 application of his general theory. What is to be under- 

 stood by the statement that matter can be neither 

 created nor destroyed ? If we mean a substratum, 

 substance itself, not identified with any physical pro- 

 perties, but the bearer of them, we remove our principle 

 from all possibility of verification and make it a bare 

 philosophical assertion with no direct relation to the 

 world of percepts, outside the domain of natural 

 science. 



This discussion is followed by a full account of the 

 recent electrical theories of the nature of matter and 

 of the various manifestations of radio-activity. Two 

 chapters discuss cosmical theories and Einstein ; four, 

 biology in general, the living organism, heredity, and 

 the evolution of species. In all, the same balanced 

 judgment is maintained, with the same readiness to 

 keep and inculcate an open mind towards the indefinite 

 expansion of scientific truth. Thus, while not accepting 

 the adequacy of any determinist scheme at our present 

 stage of thought, we are not to consider that there are 

 any barriers which will prevent " even larger tracts of 

 phenomena from being correlated with deterministic 

 descriptive schemes." In the realm of life, while 

 allowing full force to the contentions of Driesch and 

 the Neo-vitalists, he tells us that we must be prepared 

 to contemplate as a possibility that the ultimate 



