Charles Darwin: Most

“It is not the strongest of the species that survives, nor the most intelligent, but rather the one most adaptable to change.”

Charles Darwin

The earliest known appearance of this basic statement is a paraphrase of Darwin in the writings of Leon C. Megginson, a management sociologist at Louisiana State University. [[Megginson, Leon C., Lessons from Europe for American Business, Southwestern Social Science Quarterly, 1963, 44(1), 3-13, p. 4]] Megginson's paraphrase (with slight variations) was later turned into a quotation. See the summary of Nicholas Matzke's findings in "One thing Darwin didn't say: the source for a misquotation" http://www.darwinproject.ac.uk/one-thing-darwin-didnt-say at the Darwin Correspondence Project. The statement is incorrectly attributed, without any source, to Clarence Darrow in Improving the Quality of Life for the Black Elderly: Challenges and Opportunities : Hearing before the Select Committee on Aging, House of Representatives, One Hundredth Congress, first session, September 25, 1987 (1988).
Misattributed

Intelligence , Change

“I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can.”

Charles Darwin

volume II, chapter VII: "The 'Origin of Species'", pages 311-312 http://darwin-online.org.uk/content/frameset?pageseq=327&itemID=F1452.2&viewtype=image; letter http://www.darwinproject.ac.uk/entry-2814 to Asa Gray (22 May 1860)
"Ichneumonidæ" sometimes altered to "parasitic wasps" in paraphrases of this passage.
Paraphrased as "I feel most deeply that this whole question of Creation is too profound for human intellect. A dog might as well speculate on the mind of Newton! Let each man hope and believe what he can." Elbert Hubbard, Little Journeys to the Homes of Great Scientists (1916) page 197 http://books.google.com/books?id=nYArAQAAMAAJ&pg=PA198&f=false. 
The Life and Letters of Charles Darwin (1887)
Context: With respect to the theological view of the question. This is always painful to me. I am bewildered. I had no intention to write atheistically. But I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidæ with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice. Not believing this, I see no necessity in the belief that the eye was expressly designed. On the other hand, I cannot anyhow be contented to view this wonderful universe, and especially the nature of man, and to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can. Certainly I agree with you that my views are not at all necessarily atheistical.

Dogs , Hope , Feeling

“Disinterested love for all living creatures, the most noble attribute of man.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter III: "Comparison of the Mental Powers of Man and the Lower Animals — continued", page 105 http://darwin-online.org.uk/content/frameset?pageseq=118&itemID=F937.1&viewtype=image
The Descent of Man (1871)

Love

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

Charles Darwin

Men

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

Charles Darwin book The Expression of the Emotions in Man and Animals

Source: The Expression of the Emotions in Man and Animals

“In the long history of humankind (and animal kind, too) those who learned to collaborate and improvise most effectively have prevailed.”

Charles Darwin

For Team , History , Learning , Animals

“But I was very unwilling to give up my belief; I feel sure of this, for I can well remember often and often inventing day-dreams of old letters between distinguished Romans, and manuscripts being discovered at Pompeii or elsewhere, which confirmed in the most striking manner all that was written in the Gospels. But I found it more and more difficult, with free scope given to my imagination, to invent evidence which would suffice to convince me. Thus disbelief crept over me at a very slow rate, but was at last complete. The rate was so slow that I felt no distress.Although I did not think much about the existence of a personal God until a considerably later period of my life, I will here give the vague conclusions to which I have been driven. The old argument from design in Nature, as given by Paley, which formerly seemed to me so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings, and in the action of natural selection, than in the course which the wind blows. But I have discussed this subject at the end of my book on the Variation of Domesticated Animals and Plants, and the argument there given has never, as far as I can see, been answered.”

Charles Darwin

volume I, chapter VIII: "Religion", pages 308-309 http://darwin-online.org.uk/content/frameset?pageseq=326&itemID=F1452.1&viewtype=image

Francis Darwin calls these "extracts, somewhat abbreviated, from a part of the Autobiography, written in 1876". The original version is presented below.
The Life and Letters of Charles Darwin (1887)
Variant: p>But I was very unwilling to give up my belief;—I feel sure of this for I can well remember often and often inventing day-dreams of old letters between distinguished Romans and manuscripts being discovered at Pompeii or elsewhere which confirmed in the most striking manner all that was written in the Gospels. But I found it more and more difficult, with free scope given to my imagination, to invent evidence which would suffice to convince me. Thus disbelief crept over me at a very slow rate, but was at last complete. The rate was so slow that I felt no distress, and have never since doubted even for a single second that my conclusion was correct. 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 my best friends, will be everlastingly punished.And this is a damnable doctrine.Although I did not think much about the existence of a personal God until a considerably later period of my life, I will here give the vague conclusions to which I have been driven. The old argument of design in nature, as given by Paley, which formerly seemed to me so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows. Everything in nature is the result of fixed laws. But I have discussed this subject at the end of my book on the Variation of Domesticated Animals and Plants, and the argument there given has never, as far as I can see, been answered.</p

Imagination , Animals , Personality , Thinking

“The natural history of these islands is eminently curious, and well deserves attention. Most of the organic productions are aboriginal creations, found nowhere else; there is even a difference between the inhabitants of the different islands; yet all show a marked relationship with those of America, though separated from that continent by an open space of ocean, between 500 and 600 miles in width. The archipelago is a little world within itself, or rather a satellite attached to America, whence it has derived a few stray colonists, and has received the general character of its indigenous productions. Considering the small size of these islands, we feel the more astonished at the number of their aboriginal beings, and at their confined range. Seeing every height crowned with its crater, and the boundaries of most of the lava-streams still distinct, we are led to believe that within a period, geologically recent, the unbroken ocean was here spread out. Hence, both in space and time, we seem to be brought somewhat near to that great fact — that mystery of mysteries — the first appearance of new beings on this earth.”

Charles Darwin book The Voyage of the Beagle

Source: The Voyage of the Beagle (1839), chapter XVII: "Galapagos Archipelago" (second edition, 1845), entry for 8 October 1835, pages 377-378 http://darwin-online.org.uk/content/frameset?pageseq=390&itemID=F14&viewtype=image

World , Feeling , History , Nature

“Most of the more complex emotions are common to the higher animals and ourselves. Every one has seen how jealous a dog is of his master's affection, if lavished on any other creature; and I have observed the same fact with monkeys. This shews that animals not only love, but have the desire to be loved.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter II: "Comparison of the Mental Powers of Man and the Lower Animals", pages 41-42 http://darwin-online.org.uk/content/frameset?pageseq=54&itemID=F937.1&viewtype=image
The Descent of Man (1871)

Love , Dogs , Animals

“With highly civilised nations continued progress depends in a subordinate degree on natural selection; for such nations do not supplant and exterminate one another as do savage tribes. Nevertheless the more intelligent members within the same community will succeed better in the long run than the inferior, and leave a more numerous progeny, and this is a form of natural selection. The more efficient causes of progress seem to consist of a good education during youth whilst the brain is impressible, and of a high standard of excellence, inculcated by the ablest and best men, embodied in the laws, customs and traditions of the nation, and enforced by public opinion. It should, however, be borne in mind, that the enforcement of public opinion depends on our appreciation of the approbation and disapprobation of others; and this appreciation is founded on our sympathy, which it can hardly be doubted was originally developed through natural selection as one of the most important elements of the social instincts.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter V: "On the Development of the Intellectual and Moral Faculties during Primeval and Civilised Times" (second edition, 1874) page 143 http://darwin-online.org.uk/content/frameset?pageseq=166&itemID=F944&viewtype=image
The Descent of Man (1871)

Men , Youth , Education , Law

“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 on the earth, be truly enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and gravest objection which can be urged against my theory. The explanation lies, as I believe, in the extreme imperfection of the geological record.”

Charles Darwin book On the Origin of Species (1859)

Source: On the Origin of Species (1859), chapter IX: "On the Imperfection of the Geological Record", page 280 http://darwin-online.org.uk/content/frameset?pageseq=298&itemID=F373&viewtype=image

“With mankind the differences between the sexes are greater than in most species of Quadrumana, but not so great as in some, for instance, the mandrill. Man on an average is considerably taller, heavier, and stronger than woman, with squarer shoulders and more plainly-pronounced muscles. … Man is more courageous, pugnacious, and energetic than woman, and has a more inventive genius. His brain is absolutely larger, but whether relatively to the larger size of his body, in comparison with that of woman, has not, I believe been fully ascertained. In woman the face is rounder; the jaws and the base of the skull smaller; the outlines of her body rounder, in parts more prominent; and her pelvis is broader than in man; but this latter character may perhaps be considered rather as a primary than a secondary sexual character. She comes to maturity at an earlier age than man.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume II, chapter XIX: "Secondary Sexual Characters of Man", pages 316-317 http://darwin-online.org.uk/content/frameset?pageseq=333&itemID=F937.2&viewtype=image
The Descent of Man (1871)

Age , Sex , Courage , Parting

“Man bears in his bodily structure clear traces of his descent from some lower form; but it may be urged that, as man differs so greatly in his mental power from all other animals, there must be some error in this conclusion. No doubt the difference in this respect is enormous, even if we compare the mind of one of the lowest savages, who has no words to express any number higher than four, and who uses no abstract terms for the commonest objects or affections, with that of the most highly organised ape.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter II: "Comparison of the Mental Powers of Man and the Lower Animals", page 34 http://darwin-online.org.uk/content/frameset?pageseq=47&itemID=F937.1&viewtype=image
The Descent of Man (1871)

Error , Animals

“There should be open competition for all men; and the most able should not be prevented by laws or customs from succeeding best and rearing the largest number of offspring. Important as the struggle for existence has been and even still is, yet as far as the highest part of man's nature is concerned there are other agencies more important. For the moral qualities are advanced, either directly or indirectly, much more through the effects of habit, the reasoning powers, instruction, religion, &c., than through natural selection; though to this latter agency the social instincts, which afforded the basis for the development of the moral sense, may be safely attributed.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume II, chapter XXI: "General Summary and Conclusion", pages 403-404 http://darwin-online.org.uk/content/frameset?pageseq=420&itemID=F937.2&viewtype=image
The Descent of Man (1871)

Men , Religion , Law , Nature

“I believe that animals have descended from at most only four or five progenitors, and plants from an equal or lesser number.

Analogy would lead me one step further, namely, to the belief that all animals and plants have descended from some one prototype. But analogy may be a deceitful guide. Nevertheless all living things have much in common, in their chemical composition, their germinal vesicles, their cellular structure, and their laws of growth and reproduction. We see this even in so trifling a circumstance as that the same poison often similarly affects plants and animals; or that the poison secreted by the gall-fly produces monstrous growths on the wild rose or oak-tree. Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed by the Creator.”

Charles Darwin book On the Origin of Species (1859)

Source: On the Origin of Species (1859), chapter XIV: "Recapitulation and Conclusion", page 484 http://darwin-online.org.uk/content/frameset?pageseq=505&itemID=F376&viewtype=side, in the second (1860) edition

Life , Secret , Law , Tree

“Looking not to any one time, but to all time, if my theory be true, numberless intermediate varieties, linking most closely all the species of the same group together, must assuredly have existed; but the very process of natural selection constantly tends, as has been so often remarked, to exterminate the parent forms and the intermediate links. Consequently evidence of their former existence could be found only amongst fossil remains”

Charles Darwin book On the Origin of Species (1859)

.
Source: On the Origin of Species (1859), chapter VI: "Difficulties on Theory", page 179 http://darwin-online.org.uk/content/frameset?pageseq=197&itemID=F373&viewtype=side

Nature , Parent , Time

“Fitz-Roy's temper was a most unfortunate one. It was usually worst in the early morning, and with his eagle eye he could generally detect something amiss about the ship, and was then unsparing in his blame. He was very kind to me, but was a man very difficult to live with on the intimate terms which necessarily followed from our messing by ourselves in the same cabin. We had several quarrels; for instance, early in the voyage at Bahia, in Brazil, he defended and praised slavery, which I abominated, and told me that he had just visited a great slave-owner, who had called up many of his slaves and asked them whether they were happy, and whether they wished to be free, and all answered "No." I then asked him, perhaps with a sneer, whether he thought that the answer of slaves in the presence of their master was worth anything? This made him excessively angry, and he said that as I doubted his word we could not live any longer together. I thought that I should have been compelled to leave the ship; but as soon as the news spread, which it did quickly, as the captain sent for the first lieutenant to assuage his anger by abusing me, I was deeply gratified by receiving an invitation from all the gun-room officers to mess with them. But after a few hours Fitz-Roy showed his usual magnanimity by sending an officer to me with an apology and a request that I would continue to live with him.”

Charles Darwin

volume I, chapter II: "Autobiography", pages 60-61 http://darwin-online.org.uk/content/frameset?pageseq=78&itemID=F1452.1&viewtype=image
The Life and Letters of Charles Darwin (1887)

Anger , Happiness

“The lower animals, like man, manifestly feel pleasure and pain, happiness and misery. Happiness is never better exhibited than by young animals, such as puppies, kittens, lambs, &c., when playing together, like our own children. Even insects play together, as has been described by that excellent observer, P. Huber, who saw ants chasing and pretending to bite each other, like so many puppies.
The fact that the lower animals are excited by the same emotions as ourselves is so well established, that it will not be necessary to weary the reader by many details. Terror acts in the same manner on them as on us, causing the muscles to tremble, the heart to palpitate, the sphincters to be relaxed, and the hair to stand on end. Suspicion, the offspring of fear, is eminently characteristic of most wild animals. Courage and timidity are extremely variable qualities in the individuals of the same species, as is plainly seen in our dogs. Some dogs and horses are ill-tempered and easily turn sulky; others are good-tempered; and these qualities are certainly inherited.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter II: "Comparison of the Mental Powers of Man and the Lower Animals", pages 39-40 http://darwin-online.org.uk/content/frameset?pageseq=52&itemID=F937.1&viewtype=image
The Descent of Man (1871)

Pain , Children , Pleasure , Fear

“There is good evidence that the art of shooting with bows and arrows has not been handed down from any common progenitor of mankind, yet the stone arrow-heads, brought from the most distant parts of the world and manufactured at the most remote periods, are, as Nilsson has shewn, almost identical; and this fact can only be accounted for by the various races having similar inventive or mental powers.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume I, chapter VII: "On the Races of Man", pages 232-233 http://darwin-online.org.uk/content/frameset?pageseq=245&itemID=F937.1&viewtype=image
The Descent of Man (1871)

World , Art , Distant , Parting

“The chief distinction in the intellectual powers of the two sexes is shewn by man attaining to a higher eminence, in whatever he takes up, than woman can attain — whether requiring deep thought, reason, or imagination, or merely the use of the senses and hands. If two lists were made of the most eminent men and women in poetry, painting, sculpture, music, — comprising composition and performance, history, science, and philosophy, with half-a-dozen names under each subject, the two lists would not bear comparison. We may also infer, from the law of the deviation of averages, so well illustrated by Mr. Galton, in his work on 'Hereditary Genius,' that if men are capable of decided eminence over women in many subjects, the average standard of mental power in man must be above that of woman. … Thus man has ultimately become superior to woman.”

Charles Darwin book The Descent of Man, and Selection in Relation to Sex

volume II, chapter XIX: "Secondary Sexual Characters of Man", pages 327-328 http://darwin-online.org.uk/content/frameset?pageseq=344&itemID=F937.2&viewtype=image
The Descent of Man (1871)

Women , Men , Law , Music