Carlile. — On Nccessarij Truth. 645 



tirely different sort of evidence from that on which the cer- 

 tainty of the former depended. This doctrine, at any rate, 

 afforded him a basis of classification which enabled him to 

 avoid the hair-splittings and inconsistencies of the modern 

 Humist school. The great leader of that school, Mr. J. S. 

 Mill, takes all the axioms out of the class of necessary truths, 

 and puts them into the class of truths of experience ; and he 

 thus, as every one is aware, arrives at the amazing opinion 

 that we are not justified in asserting that two and two could 

 never in any possible circumstances make five. His most 

 distinguished disciple. Professor Bain, does not altogether 

 follow him here. He, indeed, takes the axiom, " Things 

 which are equal to the same thing are equal to one another," 

 with its corollaries, out of the identical or implicated class, 

 and puts it into the matter-of-fact or experience class ; but he 

 leaves others of them, such as the predication in regard to two 

 straight lines that they cannot enclose a space, in the identi- 

 cal class. Mr. Mansel, who follows Kant, and uses Kantian 

 phraseology, also puts some of the axioms in one class and 

 some in another ; but the strange thing is that the very 

 axioms which Mr. Bain takes out of the identical class Mr. 

 Mansel retains within it, and others which Mr. Bain thinks 

 fall within it he leaves outside it. Professor Huxley, following 

 Bain, says of the axiom, " Things that are equal to the same 

 thing are equal to one another," that it is only a particular 

 case of the predication of similarity — that is to say, I suppose, 

 that it is a proposition of precisely similar import to this : 

 " John is very like Thomas." It must be said, however, that 

 Professor Huxley's views altogether on necessarj^ truth and 

 cognate questions very plainly betray the amateur. He re- 

 marks in a previous chapter of his treatise* that the certain 

 reminiscence, " I was in pain yesterday," may be properly said 

 to be necessary. If that were so there would be no distinc- 

 tion whatever between truths of demonstration and facts of 

 memory ; and in that case a very great part of all that Plato, 

 Descartes, Kant, Locke, and even Hume himself have w^ritten 

 would be words to which no meaning could be attached. 

 Professor Huxley, however, only puts in the crudest form 

 what are in truth the doctrines of his school, and what are 

 professed as such, though in more guarded fashion, by its 

 acutest thinkers. Mr. Spencer, for instance, if he would not 

 call the statement, "I was in pain yesterday," a necessary 

 truth, would so denominate the statement, " I am in pain 

 now." Such statements may possess a degree of certainty 

 that cannot be exaggerated; yet a very little reflection is suffi- 

 cient to show that the evidence on which they rest is in no 



* " Hume," in the English Men of Letters Series. 



