12 THE DOCTRINE OF DESCENT. 



These groups of facts, thus mutually referring to each 

 other, must be, in some degree, examined by any one 

 desirous of understanding them. In other words, we 

 must first review this vast material, before we turn our 

 attention to the magic spell which. sifts and makes it 

 comprehensible. The toil is great, but the reward is 

 glorious ! For, as regards the organic world, the craving 

 inherent in the human mind for the knowledge of reasons 

 — the need of causality, is satisfied singly and solely by 

 the doctrine of Descent As yet we do not regard it as 

 complete ; in many special cases it still owes us an 

 answer ; but, on the whole, it does as much as any other 

 ingenious theory has done ; it interprets by a single prin- 

 ciple those great phenomena which without its aid remain 

 a mass of unintelligible miracles. In a word, it raises 

 the knowledge of organic nature to a science. Even now 

 much of mere professional knowledge is wont to style 

 itself science. But as the doctrine of Descent includes 

 all life, it cannot stop on approaching Man. Were we 

 doubtful as to the origin of language, or even forced to 

 admit total ignorance on this point, we could not, from 

 the existence of language, deduce the inapplicability to 

 man of the doctrine of Descent, without, as it seems to 

 us, arbitrarily breaking the chain of ratiocination. 



We will now return to the preliminary question already 

 indicated, as to the limits of the investigation of nature. 

 It is the more important, as incompetent judges are 

 wont to assert, that these limits are exceeded. The 

 frivolity of the logic by which such accusations are ren- 

 dered plausible to the multitude surpasses all licence. 

 We open, for instance, Luthardt's " Apologetic Lectures 

 on the Fundamental Truths of Christianity," ("Apolo- 



