530 



THE CAT. 



[chap. XV. 



human intellect which sees in the concordance between subjective 

 reason and the rational laws of the objective universe, evidence that 

 the human intellect itself has been created in the image and likeness 

 of that intellect which is Divine. 



§ 19. Our endeavour in the pursuit of knowledge should be humbly 

 but zealously to follow that natural impulse implanted in us, to 

 synthesize as well as to analyse, and above all to be untiring in the 

 pursuit of causes. Of the scientific man it may indeed be said : 



Felix qui potuit reruni cognoscere causas. 



No knowledge of mere facts and phenomena, however multitudin- 

 ous and varied, will suffice to constitute " science." The essence 

 of all science is a knowledge of causes, and only when all the 

 phenomena embraced by any given study have been referred to 

 their immediate causes, and when all their more remote causes have 

 been duly investigated, and their several inter-relations clearly 

 understood, will that study be able to take its place as a perfected 

 " science." Great has been the progress of this kind which Biology 

 has made during the last half century. Full of hope and promise 

 is the prospect before it, long as must be its course before its per- 

 fected condition can be attained. 



§ 20. To help on its progress, no course is perhaps more useful 

 than that of the careful study of a succession of types belonging to 

 different families of living beings. Amongst the multitude of such 

 groups, that one has been here selected for examination which has 

 been deemed most likely to be useful to the earnest enquirer in 

 biological science who is beginning such a course of study. No 

 more complete example of a perfectly organized living being can 

 well be found, than that supplied by a member of what has no in- 

 considerable claims to be regarded as the highest mammalian family 

 — the family Fc/idce. 



