RECENT ADVANCES IN SCIENCE 451 



important was the so-called Scottish school of common-sense, 

 which urged that it was a plain fact, not to be traversed by any 

 metaphysical subtleties, that there are two separate things, 

 mind and matter, which can by no juggling be reduced to one. 

 No more excellent idea of the tenets of these philosophers can 

 be conveyed than that set forward in the work of Mr. G. A. 

 Johnston (Selections from the Scottish Philosophy of Common 

 Sense. Edited, with an Introduction, by G. A. Johnston : 

 Open Court Publishing Co., 1915), who gives long extracts from 

 the work of Thomas Reid, Adam Ferguson, James Beattie, 

 and Dugald Stewart ; and provides a very discerning intro- 

 duction to the doctrines of these authors. The school of 

 I realism " which they founded, however, owed its popularity 

 far more to its harmoniousness with public sentiment than to 

 any true value or insight of their writings. They were fully 

 as metaphysical as Hume, whom they attacked ; but they 

 defended religion against the scepticism of that philosopher, 

 they insisted upon a divine purpose running through the 

 Universe, they set forth in philosophic language all that the 

 public most wished to hear, and they carefully avoided all 

 the genuine arguments brought forward by their great 

 antagonist, whose philosophy was far deeper and, it may be 

 added, far more Scottish than their own. 



Realism, however, is not necessarily condemned by the 

 arguments of the primitive realists. In our own day we have 

 a new realism, advocated by Mr. Bertrand Russell (Our 

 Knowledge of the External World. By Bertrand Russell, F.R.S. : 

 Open Court Publishing Co., 1914), which is of quite another 

 character from that of Thomas Reid. For us, the most 

 interesting aspect of the new realism is that it endeavours 

 to draw the whole problem within the purview of science. 

 Mr. Russell proposes to treat it by mathematics and logic ; 

 there are, however, many who think that physiology offers a 

 more hopeful prospect for the future. The conflicting views 

 on this subject must be postponed for further discussion in a 

 future paper. 



MATHEMATICS. By Philip E. B. Jourdain, M.A., Cambridge. 



The subdivisions of any science must be more or less arbitrary. 

 In the case of mathematics it is quite often fairly easy to 

 separate such subjects as geometry and applied mathematics, 



