A man who dares to waste one hour of time has not discovered the value of life.

One general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.

How paramount the future is to the present when one is surrounded by children.

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.

Freedom of thought is best promoted by the gradual illumination of men’s minds which follows from the advance of science.

It is difficult to believe in the dreadful but quiet war lurking just below the serene facade of nature.

But then arises the doubt, can the mind of man, which has, as I fully believe been developed from a mind as low as that possessed by the lowest animal, be trusted when it draws...

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.

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.

Man tends to increase at a greater rate than his means of subsistence.

The limit of man s knowledge in any subject possesses a high interest which is perhaps increased by its close neighbourhood to the realms of imagination.

A man’s friendships are one of the best measures of his worth.

One hand has surely worked throughout the universe.

He [Erasmus Darwin] used to say that ‘unitarianism was a feather-bed to catch a falling Christian.

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.

To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been...

My mind seems to have become a kind of machine for grinding general laws out of large collections of facts.

…Whilst on board the Beagle I was quite orthodox, and I remember being heartily laughed at by several of the officers… for quoting the Bible as an unanswerable authority on some point of morality… But...

An American monkey, after getting drunk on brandy, would never touch it again, and thus is much wiser than most men.

A grand and almost untrodden field of inquiry will be opened, on the causes and laws of variation, on correlation of growth, on the effects of use and disuse, on the direct actions of external...

There are several other sources of enjoyment in a long voyage, which are of a more reasonable nature. The map of the world ceases to be a blank; it becomes a picture full of the...

I have tried lately to read Shakespeare, and found it so intolerably dull that it nauseated me.

But just in proportion as this process of extermination has acted on an enormous scale, so must the number of intermediate varieties, which have formerly existed, be truly enormous. Why then is not every geological...

The publication in 1859 of the Origin of Species by Charles Darwin made a marked epoch in my own mental development, as it did in that of human thought generally. Its effect was to demolish...

As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in...

I love fools’ experiments. I am always making them.

It is often attempted to palliate slavery by comparing the state of slaves with our poorer countrymen: if the misery of our poor be caused not by the laws of nature, but by our institutions,...

It may be worth while to illustrate this view of classification, by taking the case of languages. If we possessed a perfect pedigree of mankind, a genealogical arrangement of the races of man would afford...

I am turned into a sort of machine for observing facts and grinding out conclusions.

If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find no such case.

[Alexander von Humboldt was the] greatest scientific traveller who ever lived.

But when on shore, & wandering in the sublime forests, surrounded by views more gorgeous than even Claude ever imagined, I enjoy a delight which none but those who have experienced it can understand –...

The mystery of the beginning of all things is insoluble by us; and I for one must be content to remain an agnostic.

I could show fight on natural selection having done and doing more for the progress of civilization than you seem inclined to admit. Remember what risk the nations of Europe ran, not so many centuries...

It is necessary to look forward to a harvest, however distant that may be, when some fruit will be reaped, some good effected.

What a book a devil’s chaplain might write on the clumsy, wasteful, blundering, low, and horribly cruel work of nature!

But then with me the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy. Would...

The expression often used by Mr. Herbert Spencer of the Survival of the Fittest is more accurate, and is sometimes equally convenient.

Blushing is the most peculiar and most human of all expressions.

I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection.

Englishmen rarely cry, except under the pressure of the acutest grief; whereas in some parts of the Continent the men shed tears much more readily and freely.

The following proposition seems to me in a high degree probable—namely, that any animal whatever, endowed with well-marked social instincts, the parental and filial affections being here included, would inevitably acquire a moral sense or...

It is a cursed evil to any man to become as absorbed in any subject as I am in mine.

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.

When we no longer look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension; when we regard every production of nature as one which has had...

The affinities of all the beings of the same class have sometimes been represented by a great tree.I believe this simile largely speaks the truth. The green and budding twigs may represent existing species; and...

For my own part I would as soon be descended from that heroic little monkey, who braved his dreaded enemy in order to save the life of his keeper; or from that old baboon, who,...

The highest possible stage in moral culture is when we recognize that we ought to control our thoughts.

Linnaeus and Cuvier have been my two gods, though in very different ways, but they were mere schoolboys to old Aristotle.

Besides love and sympathy, animals exhibit other qualities connected with the social instincts which in us would be called moral.