Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy.

I would give absolutely nothing for the theory of Natural Selection, if it requires miraculous additions at any one stage of descent.

It is always advisable to perceive clearly our ignorance.

The season of love is that of battle. The roots of these fights run deep.

Formerly Milton's Paradise Lost had been my chief favourite, and in my excursions during the voyage of the Beagle, when I could take only a single small volume, I always chose Milton.

Each organic being is striving to increase in a geometrical ratio . . . each at some period of its life, during some season of the year, during each generation or at intervals, has to struggle for life and to suffer great destruction . . . The vigorous, the healthy, and the happy survive and multiply.

With savages, the weak in body or mind are soon eliminated. We civilized men, on the other hand, do our utmost to check the process of elimination. We build asylums for the imbecile, the maimed and the sick. Thus the weak members of civilized societies propagate their kind. No one who has attended to the breeding of domestic animals will doubt that this must be highly injurious to the race of man. Hardly anyone is so ignorant as to allow his worst animals to breed.