DESIGN IN NATURE 23 



of knowledge.' The true scientist is aware of 

 his limitations, preserves an open mind, and 

 is equally willing to learn the true or to unlearn 

 the false. 



It is thus not only an amusement, but a 

 duty, in our rambles afield, to exercise our 

 powers of observation, and to reflect intelli- 

 gently upon what we see and hear. If we do 

 this in the right way, we cannot fail to be 

 struck with the fact that unmistakable traces 

 of design exist in all parts of Nature. Things 

 are perfectly adapted to the purposes which 

 they have to serve. This will be seen, not 

 only in adaptation to environment, which 

 might possibly be the effect of development 

 under some natural law, but also in adapta- 

 tion of structure, which could not conceivably 

 be self-produced. These indications have been 

 recognized for a long period, and furnish the 

 materials out of which theologians have built 

 that famous proof of the existence of a G-od, 

 which is familiarly called the ' argument from 

 design.' One of the most exhaustive, and 

 certainly the most eloquent, exposition of 

 this argument is that of Dr. Paley, in his 

 Natural Theology. He sums it up in these 



