"A grain in the balance will determine which individual shall live and which shall die - which variety or species shall increase in number, and which shall decrease, or finally become extinct."

"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."

"What wretched doings come from the ardor of fame; the love of truth alone would never make one man attack another bitterly."

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

"Such simple instincts as bees making a beehive could be sufficient to overthrow my whole theory."

"I have stated, that in the thirteen species of ground-finches, a nearly perfect gradation may be traced, from a beak extraordinarily thick, to one so fine, that it may be compared to that of a warbler."

"Our descent, then, is the origin of our evil passions!! The devil under form of Baboon is our grandfather."

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

"How odd it is that anyone should not see that all observation must be for or against some view if it is to be of any service!"

"...ignorance more frequently begets confidence than does knowledge..."

"Or she may accept, as appearances would sometimes lead us to believe, not the male which is the most attractive to her, but the one which is the least distasteful."

"One may say there is a force like a hundred thousand wedges..."

"In regard to the amount of difference between the races, we must make some allowance for our nice powers of discrimination gained by a long habit of observing ourselves."

"Light will be thrown on the origin of man and his history."

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

"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."

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

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

"I am convinced that natural selection has been the main but not exclusive means of modification."

"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 the what is the essence of the attraction of gravity?"

"Origin of man now proved. Metaphysics must flourish. He who understand baboon would do more towards metaphysics than Locke."

"Whilst Man, however well-behaved, At best is but a monkey shaved!"

"But I am very poorly today & very stupid & I hate everybody & everything. One lives only to make blunders."

"I have deeply regretted that I did not proceed far enough at least to understand something of the great leading principles of mathematics, for men thus endowed seem to have an extra sense."

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

"What an extraordinary thing it is, Mr. Darwin seems to spend hours in cracking a horse-whip in his room, for I often hear the crack when I pass under his windows."

"I hope that I may be excused for entering on these personal details, as I give them to show that I have not been hasty in coming to a decision."

"I think an Agnostic would be the more correct description of my state of mind. The whole subject [of God] is beyond the scope of man's intellect."

"And thus, the forms of life throughout the universe become divided into groups subordinate to groups."

"Two distinct elements are included under the term "inheritance"— the transmission, and the development of characters;"

"The power to charm the female has sometimes been more important than the power to conquer other males in battle. LAWS"

"I am dying by inches, from not having any body to talk to about insects..."

"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."

"Sexual selection will also be largely dominated by natural selection tending towards the general welfare of the species."

"Unusual degree. This family became divided eight generations"

"Sexual selection acts in a less rigorous manner than natural selection. The latter produces its effects by the life or death at all ages of the more or less successful individuals."

"Man in his arrogance thinks himself a great work, worthy of the interposition of a deity. More humble, and I believe truer, to consider him created from animals."

"If any man wants to gain a good opinion of his fellow men, he ought to do what I am doing: pester them with letters."

"This preservation of favourable individual differences and variations, and the destruction of those which are injurious, I have called Natural Selection, or the Survival of the Fittest."

"Nevertheless it is probable that the hearing rather early in life such views maintained and praised may have favoured my upholding them under a different form in my 'Origin of Species."

"Natural selection rendered evolution scientifically intelligible: it was this more than anything else which convinced professional biologists like Sir Joseph Hooker, T. H. Huxley and Ernst Haeckel."

"This preservation of favourable variations and the rejection of injurious variations, I call Natural Selection."