FITNESS WITHOUT DESIGN. 191 



as one, which, by purely mechanical compensative phe- 

 nomena, produces advantageous results. The theory of 

 descent merely casts doubts on the teleological principle 

 by withdrawing the basis for positive proof, but the 

 doctrine of selection sets it directly aside, so far as it is 

 able to extend its explanation. For natural selection 

 in the struggle for existence, the extermination of the 

 less appropriate, and the survival and perpetuation of the 

 fittest and most appropriate, is a process of mechanical 

 causality of which the steady conformity to law is 

 nowhere infringed by any teleological controlling meta- 

 physical principle. This, however, produces a result 

 essentially corresponding to design ; that is to say, it 

 naturally bestows on organisms the highest capacity 

 for life under given circumstances. Natural selection 

 solves the apparently insoluble problem of ex[)laining 

 fitness as a result, without calling in the aid of design 

 as a principle. 



In each family — for, as we have seen, what zoologists 

 once designated type, has in the doctrine of Descent 

 become the family — in each family lies the potentiality 

 of a certain grade of perfection ; and when the main 

 outline of the family character is established, we see a 

 development taking place, of which the potentiality is 

 inherent in the tendency of the character, the realization 

 and necessity in the external conditions. Hence to us 

 also, progress is development, but not towards a pre- 

 destined and pre-established harmony. Karl Ernst v. 

 Baer,^* anxious to rescue design, or at least the " pur- 

 pose" — in short, predestiny, in the evolutionary series of 

 Nature, says : " Every cause engenders a process which 

 again works on towards another purpose." But why 



