142 



NATURE 



{Dec. 19, 1878 



tion of the properties of sensible bodies ; on the hypo- 

 thesis that they are built up of ring vortices set in motion 

 by some supernatural power in a frictionless liquid : 

 b3yond which we are to suppose an indefinite succession 

 of media, not hitherto imagined by any one, each mani- 

 foldly more subtle than any of those preceding it. To 

 exercise the mind in speculations on such media may be 

 a most delightful employment for those who are intel- 

 lectually fitted to indulge in it, though we cannot see 

 ■why they should on that account appropriate the words of 

 Si.. Paul. 



Nature is a journal of science, and onc*bf the severest 

 tests of a scientific mind is to discern the limits of the 

 legitimate application of scientific methods. We shall 

 therefore endeavour to keep within the bounds of science 

 in speaking of the subject-matter of this book, remem- 

 bering that there are many things in heaven and earth 

 ■which, by the selection required for the application of 

 our scientific methods, have been excluded from our 

 pdiilosophy. 



No new discoveries can make the argument against 

 the personal existence of man after death any stronger 

 than it has appeared to be ever since men began to die, 

 351 d no language can express it more forcibly than the 

 words of the Psalmist : — 



"" His breath goeth forth, he returneth to his earth ; in 

 fliat very day his thoughts perish." 



Physiology may supply a continually increasing number 

 of illustrations of the dependence of our actions, mental 

 as well as bodily, on the condition of our material organs, 

 but none of these can render any more certain those 

 Xacts about death which our earliest ancestors knew as 

 Avell as our latest posterity can ever learn them. 



Science has, indeed, made some progress in clearing 

 ^way the haze of materialism which clung so long to 

 men's notions about the soul, in spite of their dogmatic 

 "Statements about its immateriality. No anatomist now 

 looks forward to being able to demonstrate my soul by 

 dissecting it out of my pineal gland, or to determine the 

 quantity of it by the process of double weighing. The 

 Kotion that the soul exerts force lingered longer. We 

 find it even in the late Isaac Taylor's "Physical Theory 

 of a Future State." It was admitted that one body might 

 •set another in motion ; but it was asserted that in every 

 case, if we only trace the chain of phenomena far enough 

 rfeack, we must come to a body set in motion by the direct 

 action of a soul. 



It would be rash to assert that any experiments on 

 living beings have as yet been conducted with such pre- 

 cision as to account for every foot-pound of work done by 

 a-n animal in terms of the diminution of the intrinsic 

 energy of the body and its contents ; but the principle of 

 ^e conservation of energy has acquired so much scientific 

 ■weight during the last twenty years that no physiologist 

 v^ould feel any confidence in an experiment which showed 

 a considerable difference between the work done by an 

 animal and the balance of the account of energy received 

 and spent. 



Science has thus compelled us to admit that that which 

 <21stinguishes a living body from a dead one is neither a 

 ffitiaterial thing, nor that more refined entity, a " form of 

 energy." There are methods, however, by which the 

 application of energy may be directed without interfering 



with its amount. Is the soul like the engine-driver, who 

 does not draw the train himself, but, by means of certain 

 valves, directs the course of the steam so as to drive the 

 engine forward or backward, or to stop it ? 



The dynamical theory of a conservative material system 

 shows us, however, that in general the present configura- 

 tion and motion determines the whole course of the 

 system, exceptions to this rule occurring only at the 

 instants when the system passes through certain isolated 

 and singular phases, at which a strictly infinitesimal 

 force may determine the course of the system to any one 

 of a finite number of equally possible paths, as the points- 

 man at a railway junction directs the train to one set of- 

 rails or another. Prof. B. Stewart has expounded a theory 

 of this kind in his book on " The Conservation of Energy," 

 and MM. de St. Venant and Boussinesq have examined 

 the corresponding phase of some purely mathematical 

 problems. 



The science which rejoices in the name of " Psycho- 

 physik " has made considerable progress in the study of 

 the phenomena which accompany our sensations and 

 voluntary motions. We are taught that many of the 

 processes which we suppose entirely under the control of 

 our own will are subject to the strictest laws of succes- 

 sion, with which we have no power of interfering ; and 

 we are shown how to verify the conclusions of the science 

 by deducing from it methods of physical and mental 

 training for ourselves and others. 



Thus science strips off, one after the other, the more 

 or less gross materialisations by which we endeavour to 

 form an objective image of the soul, till men of science, 

 speculating, in their non-scientific intervals, like other 

 men on what science may possibly lead to, have prophe- 

 sied that we shall soon have to confess that the soul is 

 nothing else than a function of certain complex material 

 systems. 



Men of science, however, are but men, and therefore 

 occasionally contemplate their souls from within. Those 

 who, like Du Bois-Reymond, cannot admit that sensation 

 or consciousness can be a function of a material system, 

 are led to the conception of a double mind. 



" On the one side the acting, inventing, unconscious 

 material mind, which puts the muscles into motion, and 

 determines the world's history ; this is nothing else but 

 the mechanics of atoms, and is subject to the causal law, 

 and on the other side the inactive, contemplative, remem- 

 bering, fancying, conscious, immaterial mind, which 

 feels pleasure and pain, love, and hate ; this one lies 

 outside of the mechanics of matter, and cares nothing for 

 cause and effect." 



We might ask Prof. Du Bois-Reymond which of these 

 it is that does right or wrong, and knows that it is his 

 act, and that he is responsible for it, but we must go on 

 to the other view of the case, which Dr. Stoftkraft alludes 

 to at p. 78, although by some law of the Paradoxical, he is 

 not allowed to pursue a subject which might have 

 afforded excellent sport to the Society. 



*' I feel myself compelled to believe," says the learned 

 Doctor, "that all kinds of matter have their motions 

 accompanied with certain simple sensations. In a word, 

 all matter is, in some occult sense, alive." 



This is what we may call the " levelling up " policy, 

 and it has been expounded with great clearness by Prof. 



