THE EVOLUTION-HYPOTHESIS. 435 



Aided by such facts, the conception of general evolution may 

 be rendered as definite a conception as any of our complex 

 conceptions can be rendered. If, instead of the successive 

 minutes of a child's foetal life, we take the lives of successive 

 generations of creatures — if we regard the successive genera- 

 tions as differing from one another no more than the fcctus 

 differs in successive minutes; our imaginations must indeed 

 be feeble if we fail to realize in thought, the evolution of the 

 most complex organism out of the simplest. If a single cell, 

 under appropriate conditions, becomes a man in the space of a 

 few years; there can surely be no difficulty in understanding 

 how, under appropriate conditions, a cell may, in the course 

 of untold millions of years, give origin to the human race. 



Doubtless many minds are so unfurnished with those ex- 

 periences of Nature out of which this conception is built, 

 that they find difficulty in forming it. Looking at things 

 rather in their statical than in their dynamical aspects, they 

 never realize the fact that, by small increments of modifica- 

 tion, any amount of modification may in time be generated. 

 The surprise they feel on finding one whom they last saw as 

 a boy, grown into a man, becomes incredulity when the 

 degree of change is greater. To such, the hypothesis that by 

 any series of changes a protozoon can give origin to a mam- 

 mal, seems grotesque — as grotesque as Galileo's assertion of 

 the Earth's movement seemed to his persecutors; or as 

 grotesque as the assertion of the Earth's sphericity seems now 

 to the New Zealanders. But those who accept a literally- 

 unthinkable proposition as quite satisfactory, may not un- 

 naturally be expected to make a converse mistake. 



§ 119. The hypothesis of evolution is contrasted with the 

 hypothesis of special creations, in a further respect. It is 

 not simply legitimate instead of illegitimate, because repre- 

 sentable in thought instead of unrepresentable; but it has 

 the support of some evidence, instead of being absolutely un- 

 supported by evidence. Though the facts at present assign- 



