i8 SCIENCE PROGRESS 



that has any considerable body of support, or that is in the air, 

 for these are just the topics that examiners love to set questions 

 upon, and if the text-book did not prepare students to answer 

 them, it would very speedily drop out of use and be superseded 

 by another. I take, therefore, five well-known books, whose 

 vogue is proved by the number of editions and impressions that 

 have been issued. The most popular book on Logic is, I suppose, 

 that of Dr. Fowler, now in its tenth edition. It devotes 54 pages 

 to the syllogism and none to any other form of mediate inference. 

 Prof. Carveth Read's Logic is in its fourth edition, and has 

 been reprinted ten times ; it has 52 pages on the syllogism, and 

 none on any other form of mediate inference. Mr. Welton's 

 Manual of Logic is now in the fifth impression of the second 

 edition ; it devotes 134 pages to the syllogism, and less than 

 3 pages to all the other forms of mediate inference put together. 

 The Formal Logic of Dr. Keynes, now in its fourth edition, 

 gives 146 pages to the syllogism, and 2I pages to other forms 

 of mediate inference. Dr. Mellone's Text-book of Logic, of which 

 my copy is of the third edition, gives 75 pages to the syllogism, 

 and none to any other form of mediate inference. I submit, 

 therefore, that my assertion that " the central doctrine of logic 

 is that there is only one mode of reasoning or inference, only 

 one way in which we can reason from premisses to a conclusion, 

 and that this is by means of the syllogism," cannot be seriously 

 impugned. 



"Nevertheless," says Miss Stebbing, " many of the arguments 



which he does adduce are really syllogisms in disguise — that is 



to say, they are arguments only if there be assumed premisses 



the production of which suffices to turn the argument into a 



correct syllogism." I draw attention to the sign of quantity, 



11 many," a sign, by the way, which Miss Stebbing has no business 



to use, for it is unknown to logic ; but it appears that Miss 



Stebbing, like other logicians, cannot conduct an argument 



within the boundaries of logic, but must go outside of them 



into the world of common sense. As a logician she should have 



said "some of the arguments," and although you never know 



in logic whether "some" may not be all, for logicians have 



a rooted and irrational aversion to the use of "some only," yet 



it is noteworthy that Miss Stebbing does pointedly abstain from 



asserting that all my arguments can be expressed in syllogisms. 



That some of them can be so expressed I admit, and I was quite 



