I 
WHAT ARE SPECIES 
0 
were believed to have been always as distinct and separate as 
they are now, and to have originated by some totally unknown 
process so far removed from ordinary reproduction that it was 
usually spoken of as “special creation.” There was, then, no 
question of the origin of families, orders, and classes, because 
the very first step-erf all, the “origin of species,” was believed 
to be an insoluble problem. But now this is all changed. The 
whole scientific and literary world, even the whole educated 
public, accepts, as a matter of common knowledge, the origin 
of species from other allied species by the ordinary process of 
natural birth. The idea of special creation or any altogether 
exceptional mode of production is absolutely extinct! Vet 
more: this is held also to apply to many higher groups as 
well as to the species of a genus, and not even Mr. Darwin’s 
severest critics venture to suggest that the primeval bird, 
reptile, or fish must have been “ specially created.” And this 
vast, this totally unprecedented change in public opinion has 
been the result of the work of one man, and was brought 
about in the short space of twenty years ! This is the answer 
to those who continue to maintain that the “origin of species is 
not yet discovered ; that there are still doubts and difficulties ; 
that there are divergencies of structure so great that we 
cannot understand how they had their beginning. We may 
admit all this, just as we may admit that there are enormous 
difficulties in the way of a complete comprehension of the 
origin and nature of all the parts of the solar system and of 
the stellar universe. But we claim for Darwin that he is the 
Newton of natural history, and that, just so surely as that the 
discovery and demonstration by Newton of the law of gravita¬ 
tion established order in place of chaos and laid a sure founda¬ 
tion for all future study of the starry heavens, so surely has 
Darwin, by his discovery of the law of natural selection 
and his demonstration of the great principle of the preserva¬ 
tion of useful variations in the struggle for life, not only thrown 
a flood of light on the process of development of the whole 
organic world, but also established a firm foundation for all 
future study of nature. 
In order to show the view Darwin took of his own work, 
and what it was that he alone claimed to have done, the 
concluding passage of the introduction to the Origin of 
