Charles Darwin

I never gave up Christianity until I was forty years of age.

The plow is one of the most ancient and most valuable of man's inventions; but long before he existed the land was in fact regularly plowed, and still continues to be thus plowed by earthworms. It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organized creatures.

It at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed.

You will be astonished to find how the whole mental disposition of your children changes with advancing years. A young child and the same when nearly grown, sometimes differ almost as much as do a caterpillar and butterfly.

There is no fundamental difference between man and animals in their ability to feel pleasure and pain, happiness, and misery.

We thus learn that man is descended from a hairy quadruped, furnished with a tail and pointed ears, probably arboreal in its habits, and an inhabitant of the Old World.

...I have always maintained that, excepting fools, men did not differ much in intellect, only in zeal and hard work; and I still think there is an eminently important difference.

Why does man regret, even though he may endeavour to banish any such regret, that he has followed the one natural impulse, rather than the other; and why does he further feel that he ought to regret his conduct? Man in this respect differs profoundly from the lower animals.

When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Cambrian system was deposited, they seem to me to become ennobled.

I think it inevitably follows, that as new species in the course of time are formed through natural selection, others will become rarer and rarer, and finally extinct. The forms which stand in closest competition with those undergoing modification and improvement will naturally suffer most.

We feel surprise when travellers tell us of the vast dimensions of the Pyramids and other great ruins, but how utterly insignificant are the greatest of these, when compared to these mountains of stone accumulated by the agency of various minute and tender animals!

I am actually weary of telling people that I do not pretend to adduce [direct] evidence of one species changing into another, but I believe that this view is in the main correct, because so many phenomena can thus be grouped end explained.

It may be conceit, but I believe the subject will interest the public, and I am sure that the views are original.

I can indeed hardly see how anyone ought to wish Christianity to be true for if so the plain language of the text seems to show that the men who do not believe, and this would include my father, brother and almost all of my friends, will be everlastingly punished. And this is a damnable doctrine.

The very essence of instinct is that it's followed independently of reason.

When the sexes differ in beauty, in the power of singing, or in producing what I have called instrumental music, it is almost invariably the male which excels the female.

Ultimately a highly complex sentiment, having its first origin in the social instincts, largely guided by the approbation of our fellow-men, ruled by reason, self-interest, and in later times by deep religious feelings, confirmed by instruction and habit, all combined, constitute our moral sense or conscience.

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

Language is an art, like brewing or baking.... It certainly is not a true instinct, for every language has to be learnt.

It is always advisable to perceive clearly our ignorance.

So in regard to mental qualities, their transmission is manifest in our dogs, horses and other domestic animals. Besides special tastes and habits, general intelligence, courage, bad and good tempers. etc., are certainly transmitted.