THE TEST OF TRUTH 



proposition is a concrete one, including the va- 

 riable conditions ; but although these variable 

 conditions prevent our saying that all bodies 

 will under all conditions be always and forever- 

 more expanded by heat, the case is not really 

 distinguished from the former one, since both 

 the Contingent and the Necessary Truth can 

 only be altered by an alteration in the terms. 

 If a body which does not expand by heat (there 

 are such) be brought forward as impugning the 

 truth of our proposition, we at once recognize 

 that this body is under different conditions 

 from those which our proposition included. 

 This is the introduction of a new truth, not a 

 falsification of the old. Our error, if we erred, 

 was in too hastily assuming that all bodies were 

 under the same conditions. Hence the correct 

 definition of a Contingent Truth is ' one which 

 generalizes the conditions ; ' while that of a 

 Necessary Truth is ' one which is an uncondi- 

 tional generalization.' The first affirms that 

 whatever is seen to be true, under present con- 

 ditions, will be true so long as these conditions 

 remain unaltered. The second affirms that 

 whatever is true now, being a truth irrespective 

 of conditions, cannot suffer any change from 

 interfering conditions, and must therefore be 

 universally true." ^ 



^ History of Philosophy f 4th edition, vol. i. d. cv. "^his 

 view, which I hold to be the most important coptnJ^Htion ever 



85 



