CRITICAL REMARKS, ETC. 507 



is a matter of reasonable inference ; as directly depending- on 

 the highest possible evidence it is emphatically scientific. 

 This conception was not "unmeaning" to one of the 

 greatest of human intellects, for it was that of Aristotle 

 who taught it. It is practically accepted, indeed both by 

 Weismann and Hackel. The former, as before said, 

 credits biophors with peculiar forces, while the latter is 

 ready enough to attribute an individuating- energy to every 

 cell. Why then are such forces to be denied to individual 

 animals and plants ? 



But Mr. Bourne appears to adopt a mistaken view put 

 forward by the late Professor Tyndall. The latter regarded 

 an ability to "mentally visualise" a conception as a neces- 

 sary condition of its truth. Yet to "mentally visualise" 

 anything immaterial would be a contradiction, and a "men- 

 tally visualised " notion of the kind must, by the mere fact 

 that it is so visualised, be a false notion. 



Students of science are often too ready to bow down to 

 authority and accept the dicta of men of wide repute with- 

 out examining what such dicta may be worth. They thus 

 become the victims of prejudice, forgetting that popular 

 opinion, even scientific popular opinion, is of no avail 

 against facts and logical deductions therefrom. 



It is time to protest vigorously against the statement that 

 the several departments of science should each be kept " care- 

 fully apart " from the highest department of science — from 

 that which alone gives validity to every other. Such a state- 

 ment is really as absurd as it would be to say that arith- 

 metic should be kept carefully apart from the philosophic 

 conception of "number," and geometry from that of "ex- 

 tension ". 



The impossibility of teaching physical science in terms 

 of mere phenomena has seldom been more strikingly exem- 

 plified than in Professor Pearson's recent work on physics — 

 an attempt to effect the impossible. In the conception here 

 advocated as the one only satisfactory explanation of organic 

 life, we have what no one can deny to be a vera causa, one 

 which is supremely evident in and to ourselves and which 

 we may, by the most rational analogy, extend to other 



