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.
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, not those who know much, who so positively assert that this or that problem will never be solved by science.
The love for all living creatures is the most noble attribute of man.
If the misery of the poor be caused not by the laws of nature, but by our institutions, great is our sin.
I am not apt to follow blindly the lead of other men
The mystery of the beginning of all things is insoluble by us; and I for one must be content to remain an agnostic.
The highest possible stage in moral culture is when we recognise that we ought to control our thoughts.
An American monkey, after getting drunk on brandy, would never touch it again, and thus is much wiser than most men.
We stopped looking for monsters under our bed when we realized that they were inside us.
Intelligence is based on how efficient a species became at doing the things they need to survive.
Blushing is the most peculiar and most human of all expressions.
We must, however, acknowledge, as it seems to me, that man with all his noble qualities... still bears in his bodily frame the indelible stamp of his lowly origin.
One general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.
Besides love and sympathy, animals exhibit other qualities connected with the social instincts which in us would be called moral.
In the long history of humankind (and animal kind, too) those who learned to collaborate and improvise most effectively have prevailed.
We can allow satellites, planets, suns, universe, nay whole systems of universe, to be governed by laws, but the smallest insect, we wish to be created at once by special act.
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.
Great is the power of steady misrepresentation
Man selects only for his own good: Nature only for that of the being which she tends.
I see no good reasons why the views given in this volume should shock the religious views of anyone.
...for the shield may be as important for victory, as the sword or spear.
Freedom of thought is best promoted by the gradual illumination of men’s minds which follows from the advance of science.
I am not the least afraid to die
It is not the strongest of the species that survives, not the most intelligent that survives. It is the one that is the most adaptable to change.
It is always advisable to perceive clearly our ignorance.
To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact.
There is no fundamental difference between man and animals in their ability to feel pleasure and pain, happiness, and misery.
We are not here concerned with hopes or fears, only with truth as far as our reason permits us to discover it.
The loss of these tastes [for poetry and music] is a loss of happiness, and may possibly be injurious to the intellect, and more probably to the moral character, by enfeebling the emotional part of our nature.