Charles Darwin

“ I am inclined to believe that almost every species (as we see with nearly all our domestic productions) varies sufficiently for Natural Selection to pick out and accumulate new specific differences, under new organic and inorganic conditions of life, whenever a place is open in the polity of nature. But looking to a long lapse of time and to the whole world, or to large parts of the world, I believe only one or a few species of each large genus ultimately becomes victorious, and leaves modified descendants. ”

“ If you feel any interest, or can get any one else to feel any interest on the aberrant genera question, I should think the most interesting way would be to take aberrant genera in any great natural family, and test the average number of species to the genera in that family.
How I wish we lived near each other! I should so like a talk with you on geographical distribution, taken in its greatest features. I have been trying from land productions to take a very general view of the world, and I should so like to see how far it agrees with plants. ”

“ Grant all races of man descended from one race—grant that all the structure of each race of man were perfectly known—grant that a perfect table of the descent of each race was perfectly known—grant all this, and then do you not think that most would prefer as the best classification, a genealogical one, even if it did occasionally put one race not quite so near to another, as it would have stood, if collocated by structure alone? ”

“ I must own that I have great difficulty in believing that any temporary condition of the parents can affect the offspring. If it last long enough to affect the health or structure of the parents, I can quite believe the offspring would be modified. But how mysterious a subject is that of generation! Although my hypothesis of pangenesis has been reviled on all sides, yet I must still look at generation under this point of view; and it makes me very averse to believe in an emotion having any effect on the offspring. ”

“ Before I had read your final remarks I thought also that unfavourable conditions might cause, through the law of growth, aided perhaps by reversion, degradation of character. No doubt many new laws remain to be discovered. Permit me to add that I have never been so foolish as to imagine that I have succeeded in doing more than to lay down some of the broad outlines of the origin of species.
After long reflection I cannot avoid the conviction that no innate tendency to progressive development exists, as is now held by so many able naturalists, and perhaps by yourself. ”

“ But I vehemently protest against you or any one making such cases especial marvels, without you are prepared to say why each species in any flora is twice or thrice, etc., rarer than each other species which grows in the same soil. The more I think, the more evident is it to me how utterly ignorant we are of the thousand contingencies on which range, frequency, and extinction of each species depend. ”

“ We arrived here the day before yesterday; the views of the distant mountains are most sublime and the climate delightful; after our long cruise in the damp gloomy climates of the south, to breathe a clear dry air and feel honest warm sunshine, and eat good fresh roast beef must be the summum bonum of human life. I do not like the look of the rocks half so much as the beef, there is too much of those rather insipid ingredients, mica, quartz and feldspar. ”

“ I tried to say most emphatically that a great philosopher, law-giver, etc., did far more for the progress of mankind by his writings or his example than by leaving a numerous offspring. I have endeavoured to show how the struggle for existence between tribe and tribe depends on an advance in the moral and intellectual qualities of the members, and not merely on their capacity of obtaining food. ”

“ If I think continuously on some half-dozen structures of which we can at present see no use, I can persuade myself that Natural Selection is of quite subordinate importance. On the other hand, when I reflect on the innumerable structures, especially in plants, which twenty years ago would have been called simply "morphological" and useless, and which are now known to be highly important, I can persuade myself that every structure may have been developed through Natural Selection. ”

“ My ambition is fully gratified by the satisfactory completion of my task, and I am now happy to go on jog-trot at Botany till the end of my days—downhill, in one sense, all the way. I shall never have such another object to work for, nor shall I feel the want of it...As it is, the craving of thirty years is satisfied, and I now look back on life in a way I never could previously. ”

“ I should be sorry to give up the view that an old and very large continuous territory would generally produce organisms higher in the competitive sense than a smaller territory. I may, of course, be quite wrong about the plants of Australia (and your facts are, of course, quite new to me on their highness) , but when I read the accounts of the immense spreading of European plants in Australia, and think of the wool and corn brought thence to Europe, and not one plant naturalised, I can hardly avoid the suspicion that Europe beats Australia in its productions. ”

“ But I must just say that if sterility be allowed to come into play, if long-beaked be in the least degree sterile with short-beaked, my whole case is altered. By the way, my notions on hybridity are becoming considerably altered by my dimorphic work. I am now strongly inclined to believe that sterility is at first a selected quality to keep incipient species distinct. If you have looked at Lythrum you will see how pollen can be modified merely to favour crossing; with equal readiness it could be modified to prevent crossing. ”

“ Let me first say that no man could have more earnestly wished for the success of Natural Selection in regard to sterility than I did; and when I considered a general statement (as in your last note) I always felt sure it could be worked out, but always failed in detail. The cause being, as I believe, that Natural Selection cannot effect what is not good for the individual, including in this term a social community. It would take a volume to discuss all the points, and nothing is so humiliating to me as to agree with a man like you (or Hooker) on the premises and disagree about the result. ”

“ This latter rock seems to form the nucleus of the whole mass, and is seen in the deep lateral valleys, injected amongst, upheaving, overturning in the most extraordinary manner, the overlying strata. The stratification in all the mountains is beautifully distinct and from a variety in the colour can be seen at great distances. I cannot imagine any part of the world presenting a more extraordinary scene of the breaking up of the crust of the globe than the very central parts of the Andes. ”

“ What you say about no one realising creation strikes me as very true; but I think and hope that there is nearly as much difference between trying to find out whether species of a genus have had a common ancestor and concerning oneself with the first origin of life, as between making out the laws of chemical attraction and the first origin of matter. ”

“ Everything is in flames—the sky with lightning, the water with luminous particles, and even the very masts are pointed with a blue flame. I expect great interest in scouring over the plains of Monte Video, yet I look back with regret to the Tropics, that magic lure to all naturalists. The delight of sitting on a decaying trunk amidst the quiet gloom of the forest is unspeakable and never to be forgotten. ”

“ The difficulty seems to be increased by the consideration that the advantage of a cross with a distinct individual is gained just as well by illegitimate as by legitimate unions. By what means, then, did illegitimate unions ever become sterile? It would seem a far simpler way for each plant's pollen to have acquired a prepotency on another individual's stigma over that of the same individual, without the extraordinary complication of three differences of structure and eighteen different unions with varying degrees of sterility! ”

“ WE do nothing of the sort; for WE rest on scored rocks, old moraines, arctic shells, and mammifers. I have no theory whatever about cause of cold, no more than I have for cause of elevation and subsidence; and I can see no reason why I should not use cold, or elevation, or subsidence to explain any other phenomena, such as distribution. I think if I had space and time I could make a pretty good case against any great continental changes since the Glacial epoch, and this has mainly led me to give up the Lyellian doctrine as insufficient to explain all mutations of climate. ”

“ Such men as you and Lyell thinking that I make too much of a Deus of Natural Selection is a conclusive argument against me. Yet I hardly know how I could have put in, in all parts of my book, stronger sentences. The title, as you once pointed out, might have been better. No one ever objects to agriculturalists using the strongest language about their selection, yet every breeder knows that he does not produce the modification which he selects. My enormous difficulty for years was to understand adaptation, and this made me, I cannot but think, rightly, insist so much on Natural Selection. ”

“ I feel all the time on the borders of a circle of truism. Of course I could not think of such a request, but you might possibly:—if Bentham does not think the whole subject rubbish, ask him some time to pick out the dozen most anomalous genera in the Leguminosae, or any great order of which there is a monograph by which I could calculate the ordinary percentage of species to genera. ”

“ Under the many conditions of life which this world affords, any group which is numerous in individuals and species and is widely distributed, may properly be called dominant. I never dreamed of considering that any one group, under all conditions and throughout the world, would be predominant. How could vertebrata be predominant under the conditions of life in which parasitic worms live? What good would their perfected senses and their intellect serve under such conditions? ”

“ But, oh Lord! how little we do know and have known to be so advanced in knowledge by one theory. If we thought ourselves knowing dogs before you revealed Natural Selection, what d—d ignorant ones we must surely be now we do know that law. ”

“ As you say, I have been thoroughly well attacked and reviled (especially by entomologists—Westwood, Wollaston, and A. Murray have all reviewed and sneered at me to their hearts' content) , but I care nothing about their attacks; several really good judges go a long way with me, and I observe that all those who go some little way tend to go somewhat further. What a fine philosophical mind your friend Mr. Wallace has, and he has acted, in relation to me, like a true man with a noble spirit. ”