False facts are highly injurious to the progress of science, for they often endure long but false views, if supported by some evidence, do little harm, for every one takes a salutary pleasure in proving their falseness.
What a book a devil's chaplain might write on the clumsy, wasteful, blundering, low, and horribly cruel work of nature!
An American monkey, after getting drunk on brandy, would never touch it again, and thus is much wiser than most men.
A man who dares to waste one hour of time has not discovered the value of life.
Ignorance more frequently begets confidence than does knowledge: it is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science.
In the long history of humankind (and animal kind, too) those who learned to collaborate and improvise most effectively have prevailed.
If the misery of the poor be caused not by the laws of nature, but by our institutions, great is our sin.
To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact.
I cannot persuade myself that a beneficent and omnipotent God would have designedly created parasitic wasps with the express intention of their feeding within the living bodies of Caterpillars.
At some future period, not very distant as measured by centuries, the civilized races of man will almost certainly exterminate, and replace the savage races throughout the world.
How paramount the future is to the present when one is surrounded by children.
It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to change.
A man's friendships are one of the best measures of his worth.