160 PART IV. PREPARATORY STAGE. . 



part discussed the Aristotelian logic, and the second part induc- 

 tive logic. 



To the man of science unfamiliar with text-books on logic, 

 but frequently having recourse to deduction in his scientific 

 labours, it would naturally occur to examine the first part of 

 one of those works on logic with a view to finding a detailed 

 exposition of the deductive method. Considering that there is 

 almost a consensus of opinion among logicians in regard to the 

 signal superiority of deduction over induction ( 49), this scholar 

 would anticipate a forcible and somewhat exhaustive treatment 

 of the subject. He would be therefore amazed when he dis- 

 covered scarcely a trace of anything directly dealing with, or 

 having a bearing on, what he calls deduction. Anxious to be 

 fair, he would be perplexed at the title of the books and marvel 

 what the Aristotelian logic had to do with deduction. Admirable 

 this logic is in its way, he would argue, but that it is a stranger 

 to the process of deduction in science is patent. 



On further reflection he may reason that possibly, however 

 inconsistent it might appear, the problem of deduction is ade- 

 quately examined in the second part of these works, that is in 

 the part relating to induction. Turning to this, he will probably 

 discover pertinent references, but of the scantiest kind. Leav- 

 ing aside theoretical discussions of the precise signification of 

 the terms induction and deduction, he will presumably not find 

 half-a-dozen pages allotted to the subject, all save a page or so 

 being devoted to a general survey. Having virtually consulted 

 every recent volume on logic, he will wonder what advantage 

 accrues to young students who master any of these treatises. 

 Certainly, so far as deductive procedure in science is concerned, 

 they could scarcely know less after studying such manuals than 

 they knew before. 



Thoroughly aroused, our man of science sets himself the 

 laborious task to learn what these manuals do teach. Having 

 completed his enquiry, we may imagine him summing up his 

 conclusions in this manner: "The Aristotelian logic, exhaus- 

 tively dealt with in the first part of these volumes, has, mani- 

 festly, a definitely practical object to ensure, so far as mere 

 reasoning about matters completely known is concerned, that 

 conclusions should be systematically tested by a certain pro- 

 cess. Tacitly or overtly, however, the hoary custom of re- 

 quiring students to assimilate the Aristotelian logic, has degene- 

 rated into a mere memorising and understanding of the text. 

 For sundry dubious reasons, the palpable and justifiable object 

 of the discipline is ignored or disputed. In our scientific age, 

 this logic may go but a little way; but intelligently appre- 

 hended, it is worth being acquainted with. What strikes one 

 in this respect, is how alarmingly illogical logicians can be, 

 discussing a plainly practical treatise as if it were a work 

 having not the remotest connection with practice. 



