IN TRODUC TION. xxi 



To pass from the language of metaphor to lan- 

 guage simple and unadorned, our great, or more 

 truthfully our greatest enemy, in the intellectual 

 world to-day, is Naturalism variously known as Ag- 

 nosticism, Positivism, Empiricism which, as Mr. 

 Balfour well observes, " is in reality the only system 

 which ultimately profits by any defeats which the- 

 ology may sustain, or which may be counted on to 

 flood the spaces from which the tide of religion has 

 receded." ' 



It is Naturalism that, allying itself with Evolution, 

 or some of the many theories of Evolution which 

 have attracted such widespread attention during the 

 last half century, has counted such a formidable fol- 

 lowing that the friends of religion and Scripture 

 might well despair of final victory, did they not know 

 the invincibility of truth, and that, however it may be 

 obscured for a time, or however much it may appar- 

 ently be weakened, it is sure to prevail and in the 

 end issue from the contest triumphant. 



In writing the present work I have ever had be- 

 fore my mind the words of wisdom of our Holy 

 Father, Leo XIII, concerning the duty incumbent 

 on all Catholics, to turn the discoveries of science into 

 so many means of illuminating and corroborating the 

 teachings of faith and the declarations of the Sacred 

 Text. In public and in private, in season and out of 

 season, in briefs, allocutions and encyclicals, he has 

 constantly and strenuously urged a thorough study 

 of science in all its branches. But nowhere does 

 he insist more strongly on the profound study of 



1 "The Foundations of Belief," p. 6. 



