It is not the biggest, the brightest or the best that will survive, but those who adapt the quickest.

It is like confessing to a murder.

It is no valid objection that science as yet throws no light on the far higher problem of the essence or origin of life. Who can explain gravity? No one now objects to following out the results consequent on this unknown element of attraction.

We are optimists, until we are not.

We have seen that the senses and intuitions, the various emotions and faculties, such as love, memory, attention and curiosity, imitation, reason, etc., of which man boasts, may be found in an incipient, or even sometimes in a well-developed condition, in the lower animals.

If I had my life to live over again, I would have made a rule to read some poetry and listen to some music at least once every week.

Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult--at least I have found it so--than constantly to bear this conclusion in mind.