APPENDIX A XLIX 



Philosophy is an experimental and not an intuitive science. "No à prion 

 reasoning can conduct us demonstratively to a single physical truth." 



"I hold, on the contrary," says Spencer "that as there are à priori 

 " mathematical truths the consciousness of which results, not from our 

 " individual experiences, but from the organized and inherited effects of 

 " ancestral experiences, received throughout an immeasurable past ; so 

 " there are à priori physical truths, our consciousness of which has a like 

 " origin, I have endeavoured to show that Prof. Tait, himself by say- 

 " Lug of physical axioms that the appropriately cultivated intelligence 

 " sees at once tlieir necessary truth, tacitly classes them with mathema- 

 " tical axioms of which this self-evidence is also the recognized character: 

 " Further I have contended that the Laws of Motion are à priori truths 

 "of this kind; are enunciated by Newton as such" — Spencer then goes 

 on to quote Taifs reason for a.sserting that the Laws of Motion are not to 

 be accepted as valid à priori. " The reason is that as the properties of 

 " matter might have been such as to render a totally different set of laws 

 " axiomatic, these laws must be considered as resting' on observation and 

 "' experiment, and not on intuitive perception." This is also the opinion 

 of Newton as expressed in his letters. If Herbert Spencer had ever 

 lectured to a class of students on the Second Law of Motion he might 

 have been tempted to explain their want of intuitive perception of its à 

 priori truth by a limitation of the "immeasurable past" in their 

 " ancestral experiences," and put the origin of man as recent. 



The position of Spencer in the disputation was like that of an army 

 which while fighting the enemy in front is unexpectedly assailed in the 

 flank by a force called in as an auxiliar}^ But Spencer did not quail. 

 He faced tlie new foe with undaunted courage, supported probably by 

 the conviction that while his adversary seemed to be on his own territory 

 of Physics, he was on the very verge, if he had not actually crossed the 

 boimdary line of Metaphysics, a department which borders on all the 

 Physical and Natural sciences, and appears to have to some students in 

 these departments the fascinating advantage for polemic purposes of a 

 general absence of axioms (i.e., of propositions universally admitted). 

 Hence combatants with differing opinions can each choose his own 

 axioms i.e assumptions, to support his own views, and confound adver- 

 saries. Much logomachy may thus leave general satisfaction. No one 



is confuted. , , , 



Alchemy. 



Passing on from a consideration of the uses of the Society to recent 

 progress in science, in which Canada like all the rest of the world, is in- 

 terested; and more perhaps, than most of it, in one division of the do- 

 main of Physics, we shall come casually on other rather surprising in- 



Proc, 1906. 4. 



