Why do some die and some live? The answer was clearly, that on the whole the best fitted live. From the effects of disease the most healthy escaped; from enemies, the strongest, swiftest, or the most cunning; from famine, the best hunters or those with the best digestion; and so on. Then it suddenly flashed upon me that this self-acting process would necessarily improve the race, because in every generation the inferior would inevitably be killed off and the superior would remain-that is, the fittest would survive.

Truth is born into this world only with pangs and tribulations, and every fresh truth is received unwillingly.

I hold with Henry George, that at the back of every great social evil will be found a great political wrong

As well might it be said that, because we are ignorant of the laws by which metals are produced and trees developed, we cannot know anything of the origin of steamships and railways

But naturalists are now beginning to look beyond this, and to see that there must be some other principle regulating the infinitely varied forms of animal life.

I think I have fairly heard and fairly weighed the evidence on both sides, and I remain an utter disbeliever in almost all that you consider the most sacred truths... I can see much to admire in all religions... But whether there be a God and whatever be His nature; whether we have an immortal soul or not, or whatever may be our state after death, I can have no fear of having to suffer for the study of nature and the search for truth.

What birds can have their bills more peculiarly formed than the ibis, the spoonbill, and the heron?