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He goes on to speak of the duel between the financier and the anarchist. 

 The writer recognises the need for some sort of compromise, but Bolshevism 

 which he scarcely mentions, is neither Anarchism, nor Syndicalism, nor Guild 

 Socialism. 



The last section presents a series of clever diagrams, showing the parallel, yet 

 opposing, forces in the State. But it is hardly right to call the Radicals, Socialists, 

 and Anarchists, the Party of Progress, at any rate of cautious Progress. Call 

 them rather the Party of Disorder. There is one in every State : there always 

 has been, and there always will be. The writer concludes with an appeal to the 

 nations of Europe to combine to form a real Society of Nations, containing the 

 virtues of every people. But would it not be as well to see what we can do with 

 our own country first ? 



C. C. R. 



An Enquiry Concerning the Principles of Natural Knowledge. By 



A. N. Whitehead, Sc.D., F.R.S. [Pp. xii + 200, with 19 illustrations.] 

 (Cambridge University Press, 1919. Price 12s. bd. net.) 



The recent striking confirmation of Einstein's theory by the observations carried 

 out during the total solar eclipse of May of this year has been heralded as a 

 revolution in science, and as the deposition of the traditional view of physical 

 nature. To the practical scientist Einstein's theory will mean at present very 

 little reconstruction. The main facts and resultant generalisations of physical 

 science remain valid, except for certain corrective terms, generally very minute. 

 Revolution will result rather in the philosophic basis of our view of physical 

 nature, in that the principle of relativity, readily accepted by all thinking people 

 as regards space, will be extended to include time ; and this does not in fact take 

 us much further than the "restricted theory" enunciated by Einstein in 1905, and 

 so brilliantly interpreted by Minkowski. 



Prof. Whitehead's aim is to raise the problems involved in such a recon- 

 struction, and the question that he asks himself is : "What are the ultimate data 

 of science?" He divides his enquiry into four main branches. He first disposes 

 of the traditional conception of the durationless instant of time, and the consequent 

 implication of an absolute time : what we are aware of in external nature is a 

 duration. The author then identifies the data of science as events and objects. 

 The structure of events provides the framework of the external nature within 

 which objects are located. What we perceive are spatio-temporal relations of 

 material — time, space, and material being in fact the relations between events. 

 Thus time and space are abstractions expressive of certain qualities of the structure 

 of events. Then follows the discussion of events by what Prof. Whitehead 

 calls the method of extensive abstraction, events being classed according to their 

 K-quality, or quality of extension in spatio-temporal relationship. The analytic 

 geometry of motion is investigated by the transformation from one consentient 

 set to another, based on the principle of kinematic symmetry. Three types of 

 kinematics are shown to be possible, differentiated as : (i) elliptic, in which no 

 distinction exists between time and space, so that it is inapplicable to nature ; 

 (ii) parabolic, the ordinary Newtonian common-sense system ; (iii) hyperbolic, 

 corresponding to the Larmor-Lorentz-Einstein transformation, for which the 

 electromagnetic equations are invariant. The enquiry concludes with the theory 

 of objects. An interesting outcome of Prof. Whitehead's train of ideas is the 



