I04 



NA TURE 



\_yune II, 1874 



nature of the contioveisy in order to counteract the effect of Mr. 

 Spencer's endeavours torepresent it as a controversy between those 

 who think that forms of thoiiglit become hereditary and those wlio 

 do not. The original attack centred upon the fallacious character of 

 certain would-be <! /;vi)77 proofs of physical laws. Mr. Spencer has 

 tried to parry the attack by maintaining that the writer misunder- 

 stood the sense in which the phrase a priori was used. That the 

 new interpretation was not the one which it was at the time in- 

 tended to bear is rendered as clear as the English lanjjuage per- 

 mits by his speaking of one of these truths as «d/ resulting "frum 

 a long registry of experiences gradually organised into an irre- 

 versible mode of thought,'' and his using similar, or even 

 stronger expressions of the others. But this is, after all, not the 

 real issue. No definition of a priori would cure the fallacies in 

 the proofs in question or in the subsequent attempts tliat he 

 lias made to support them. They are as illogical witli the 

 one definition as witli the other ; and the sole result of Mr. 

 Spencei's change of front v^ill be, I think, to supply the critics of 

 his writings on Physics with another instance of his habit of 

 changing the meanings of the terms he employs without per- 

 ceiving that by so doing he forfeits the right to use previous 

 conclusion?, even though legitimately obtained, and destroys all 

 connection between the bases and the later parts of his system. 



As 1 have alreadj said, I have been chiefly addressing myself to 

 Mr. Spencei's readers. My aim has been to show that his wiitiogs 

 on Pliysics are marred by superficial and inconsistent views 

 of the subject-matter and fallacies in reasoning thereon. I have 

 been accused of being too violent in my language, and some of 

 my friends have urged, like Mr. Haywaid, that it would have 

 been better had I used expressions which le s adequately con- 

 veyed my (and their) opinion of the ra.'.gnitude of the errors I 

 was attacking. As I have left the department of personal abuse 

 wholly to Mr. Spencer, I do not think he has much right to 

 complain, even though I have not hesitated to call absurdities 

 by what seemed to me descriptive and suitable titles, and I will 

 conclude this by calling attention to a last effort by Mr. Spencer 

 to show that there is some excuse for expressive language 

 on my part, provided always it is directed to the blunder rather 

 than to the blunderer. 



In Nature, vol. ix. p. 461, Mr. Spencer asserted that the 

 second law of motion was a mere corollary from the general 

 postulate that cause and effect are necessarily connected together, 

 and in all cases liy definite quantitative relations. As every ma- 

 thematician will at once see that there is a great difference 

 between asserling that there is some definite relation between 

 cause and effect and asserting that thi^ relation is the parlicidar 

 one of direct proportionality, it will be asked how he came to 

 consider the one a mere deduction from the other? It will be 

 seen, on examination of the passage, that he is misled by a 

 couple of instances that he cites (and of course he might have 

 cited countless others), where there is this simple relation be- 

 tween a prominent part of the cause and a prominent part of the 

 effect. The fallacy of this was pointed out by a writer who signed 

 himself " A .Senior Wrangler" in the next number of N.^ture, 

 and to this Mr. Spencer replies in the number for May 7 : — 



" Nor should I care to discuss any question with my new 

 anonymous assailant, who, when certain examples given shoiv the 

 ' exnet qtiantitalive relations spoken of to he those of dinxt p'opor- 

 to«,' describes me as ' intensely unmathematical,' because I sub- 

 sequently use the more general expression as equivalent to the 

 more special — which, in the case in (Question, it is." 



Now, in the first place, the phrase "certain examples show," 

 amounts to admitting that the argument is inductive in its 

 nature, which is inconsistent, to say the least, with the pro- 

 fessions he makei, for the proof is not only not to be an induc- 

 tive one, but is to render it clear that no such proof of the 

 matter in ques'.iou could possibly exist ; but this is a trifle to 

 that which follows it. Can anyone avoid admitting that the 

 italicized words leave Mr. Spencer committed to at least one of 

 the following propositions : — 



1. That these (and similar) instances establish the propo- 

 sition that the ' exact quantitative relations ' between cause and 

 effect are, in ait eases, those of direct proportionality. 



2. That in a proof (other than an inductive one) you may 

 assume the result during the progress of the argument without 

 invalidating the proof. 



The first of these is saved from being pronounced contrary 

 to fact hy being discovered, on closer examination, to be 

 meaningless ; nothing but the most superficial notions of the 

 meanings of the words cause and effect can prevent its being 

 seen to be unmeaning. The second is too common a logic d 



enor to need exposing. What examiner in Euclid has not 

 rejected attempts at the solution of geometrical deductions for 

 this fallacy? If a boy has to prove a triangle to be equilateral, 

 cruel mathematicians do not allow him to assume that it is so in 

 the course of his proof. But Mr. Spencer would take a more 

 lenient view of the matter, and would allow him to use " the 

 more general expression [i.e. triangle) as equivalent to the more 

 special {i.e. equilateral triangle), which, in t/ie ease in qusstion, 

 it is." 



The Author of the Article on Herbert Spencer 



IN THE British Quarterly Review. 



Mr. Collier, in his anxiety to "transfix" me on one of the 

 horns of a dilemma, has shown himself strangely blind to the fact 

 that he could only do so by thrusting at me through the body of 

 his leader, Mr. Spenc;r. My wound is consequently but skin 

 deep ; but what of Mr. Spencer's ? 



As I have carefully avoided representing Mr. Spencer other- 

 wise than by quoting his own words, the charge of " misrepre- 

 sentation " (an ugly word, which, I think, Mr. Collier, on recon- 

 sideration, will regret having used) falls to the ground ; and if, 

 as Mr. Collier clearly enough shows, there be inconsistency in 

 the phraseology used by Mr. .Spencer at different times, the re- 

 sponsibility rests with Mr. Spencer and not with me. 



The facts are briefly these : — Mr. Spencer first asserted the 

 Second Law of Motion to be an "immediate eorollaryof the pie- 

 eonception," &c. I criticised the assertion. Mr. Spencer charac- 

 terised my criticism as a proposal to " exemplify unconsciously- 

 formed preconceptions." I did not care for the moment to quarrel 

 with this description lest I should multiply and thus "confuse 

 the issues " between us ; and so adopting the phrase under the 

 safeguard (insufficient as it now appears to have been, at least for 

 Mr. Collier) of the usual marks of quotation, I noted what 

 appeared to me an admission, implied in Mr. Spencer's remarks, 

 and important as bearing on the real issue between us, that the 

 .Second Law of Motion is a ^^consciously-formed livpo'.hesis." 

 Mr. Collier has done well in calling attention to the discrepa'icy 

 between the first two phrases italicised. He might also have 

 noted the discrepancy between both of these and the third. But 

 the phrases are Mr. Spencer's ; and the only crime to which I 

 can plead guilty is that of not having seen the necessity of more 

 explicitly repudiating Mr. Spencer's characterisation of my criti- 

 cism, and thus saved Mr. Collier froiii bringing charges against 

 rae of " confusing issue.'," &c., which I can only transfer to Mr. 

 Spencer. 



And now having cleared the path of the personal questions 

 which Mr. Collier has raised, I would appeal to him to obtain 

 for me and other perplexed readers of Nature an authoritative 

 statement as to what Mr. Spencer's latest views as to the Second 

 Law of Motion are. Does .Mr. Spencer regard it as an "uncon- 

 sciously-formed preconception," or as a " corollary of a precon- 

 ception," or as a "consciously formed hypothesis?" Each of 

 these views seems to be deducible from Mr. Spencer's language, 

 but I agree with Mr. Collier that they can hardly be regarded 

 as one and the same thing. 



I W'ould also remind Mr. Collier that no answer has yet been 

 given to the difficulties which in my fir-t note I showed to attach 

 to the view of the Second Law of Motion as a "corollary of a 

 particular preconception ; " and tha', unless Mr. Spencer, or Mr. 

 Collier on his behalf, can show that these difficulties are imagi-- 

 nary, judgment will be recorded against them by default by all 

 readeis of Natuije who have had p.itience to follow the contro- 

 versy thus far. RoiiT. V,. Havward 



Harrow, June 6 



I ought to thank Mr. Collier for the care wiiii which he has. 

 explained his previous letter, but to assure him at the sime time 

 th.rt I fully understood it before ; his italics b.ave only made 

 plain what was accurately and lucidly expressed before, and have 

 only served to convince me that 1 thoroughly understand his 

 position, and that it is wholly untenable. 



I will make one more effort to .show this, by pointing out one 

 of the fallacies in Mr. Collier's last letter. He says "Mr. 

 Spencer alleges that this cognition of proportionality is a priori ; 

 his opponents aflitm that this cognition is ii posteriori.'" 



The " cognition " spoken of is not one, but two. Mr. Spencer 

 alleges that a conviction of a quantitative relation of some kind 

 between cause and eflect, such that the greater cause produces 

 the greiiter effect, grows in our minds from experiences wdiich 

 are aniecedent to reasoning. No one denies it. But to call this 

 a cognition of proportionality is so utterly inaccurate an expres- 

 sion as to astound me. And the consequences of the inaccuracy 



