From J. D. Hooker [23 March 1862]1
My dear Darwin
I returned last night & found Bates’ letters which I send herewith,2 I have no time to compare them— I hope I have not abused you unmercifully in my letter to Bates— you must take your chance!
I had a very profitable stay at Walcot considering all things & came away with food for much reflection.3 I could not make up my mind to stay over Sunday, though kindly pressed with real English hospitality— Some of the family are very nice—all the Ladies particularly so, the Servants perfection (such Nat: selection of flunkies)—the food good & plenty. The country beautiful—the weather detestable—& the habits & hours of the house quite intolerable— it would take a letter from you every morning to have supported me under such a system of killing time & outraging the stomach— However it does one good to go to such places rarely, gives one much food for reflection & will add a chapter to my posthumous work “On the principles which regulate the development of an Aristocracy”.4 The principle part of this work will consist of 4 chapters, each headed with a B. viz. Blood, Blunt,5 Brains, Beauty.— These are all good things, of use to the organism possessing them, & hence sought after by all human organisms, & their accumulation, by Natural Selection, must culminate in an Aristocracy—or there is no truth in darwinism. The better these are blended, the better will be your Aristocracy—the more they are seperated the worse. & it is hard to say which is worst per se, or which is best when all are mixed.
You have the Aristocracy purely of B1 in Germany; of B.2 in America, of B.3 in France, of B.4 everywhere. but of 4B in England only: where indeed we have 4B[SUPERSCRIPT 4] in the highest nobility. I met nothing beyond B1 & B2 at Walcot, however, perhaps with ever so small an element of the two others I might have been induced to stay Sunday, for I do maintain that the union of all must be irresistable, in every degree & condition of life, from Fuegia to London.
I have no time to answer your kind long letter received at Walcot.—6 There must be, as you say something effective in the alteration of the reproductive system under variation—but I do not see why, that is not a form of variation, not necessarily induced by domestication but accompanying some variety artificially selected. I cannot however forget that it is through marriage alone that the 4Bs. are usually recruited in after life & so there may be something in what you say!!! That’s my philosophy— make the best of it, till we meet.
We are concerned to hear of Horace,7 but after Ettys recovery “nil desperandum”—8 does he get regular exercise 2–3 times a day & very regular nutritious food— I do not give much for Hollands opinion.9
My wife likes the idea of my taking Willie down with me.10 pray thank Mrs Darwin very much— I have only one condition—that Mrs Darwin would let him sleep with me— I have seen nothing of him by myself since he was 6 years old & I should like to have him beside me when I am dressing. I find Charlie’s intellect singularly active in the morning.11
Ever yours affec | J D Hooker
Kew Feby 2d/62 My dear Mr Bates
I have been thinking much of your extremely interesting letter before answering it,12 & shall be only too glad if I can say any thing that can tend to remove any difficulties. I need hardly commence by telling you that my opinions are nothing, that the whole question wants working out by observation as you are doing, & by experiments which no one has attempted or even suggested that I know of— What I have said & shall now say you must take not as opinions of mine, but as my tendencies of thought.— Certainly I incline to believe that variation is sufficient to ensure any amount of divergence & that it (the principle or fact called variation) is independent wholly as to amount & kind of local circumstances.
My reasons for thus thinking are 1.) That it has never been shown experimentally that induced habits of the individual are propagated 2) That no such effects of local circumstances on the individual is necessary.— there being variation enough without it. 3) It seems more philosophical to suppose that the principle of variation is one thing, immutable, & that local circumstances are the secondary causes acting through Nat. selection on the varieties killing some sparing some directing intermarriages &c &c. 4) that it would simplify matters very much if we could thus disentangle the two phenomena of variation & Nat selection. I grant that not one of these reasons has a leg to stand upon in a strictly scientific point of view—they are a string of hypotheses, & further there are some seemingly opposed facts. 1. hereditary diseases might have been originally induced by local causes; though I think they may be explained without. It is said that a peculiar form of teeth becomes hereditary in syphilitic families.—but I suspect that this could not be perpetuated—it could only be propagated by intermarriage of children of syphilitic parents, which would surely die out.— Then too I have heard that Dr. Brown-Sequard has induced epilepsy in rabbits, & this has happened in the brood.—13 if really so this is a strong point; but here again any attempt to perpetuate the brood of epileptics must end in extinction. All these are cases of induced diseases of the individual being propagated;—could induced innocuous peculiarities be so propagated?— Englishmen show no tendency to beardless faces after 4 generations of shaving—& a thousand similar instances may be quoted—the oldest custom of all—circumcision has had no effect on the organ of the race, after hundreds of generations: which I have always regarded as the most wonderful fact.— Again though the habit of inducing varieties in plants & animals has gone on from time immemorial no one has ever supposed that one place is better than another causing the first brood to vary— Whoever plants most gets most varieties i.e secures most new sorts by after selection &c &c &c— To put the question in its simplest form—no one ever supposed that of 12 peas in one pod, 6 grown in England would be more different inter se or from their parents than the other 6 grown in Australia. Again as I have remarked in the Introd: Essay to New Zealand, the trueness with which seeds from all parts of the world come up in our gardens is astounding—14 Whoever heard of a new species thus raised by the first sowing— Were it otherwise—did individual seeds come up differently in different localities—you would surely in extreme cases have different species & different genera coming up at once in our gardens— On the other hand—Rivett wheat seed produces Rivetts in Australia the first year; but whereas even Rivett wheat has its varieties & and some of them are more suited to Australia than England, after several generations the Rivetts of Australia will differ from those of England, but through Natural Selection.— In all these considerations we must carefully exclude mere stunting or the effect of overgrowth & undergrowth, which are not variations in the sense I allude to, though I confess to my inability of pointing out any scientific distinction that is irrefragable.
Now all your apparent exceptions are I grant very strong cases at first sight; but may all be explained by assuming more time than you do, & correcting more than you do for the millions of lost individuals. That “species will be constant under one set of conditions & variable under another” is quite true—but this is no proof that even extreme external physical conditions have acted on the pregnant female so as to have produced greater differences amongst her ova.—or on the sperm cells of the male previously.—to an extent perceptible in the first brood.
I have long on other grounds denied that tropical heat or light produces the bright coloring of plants, or that arctic climates produce woolly covering.—15 these phenomena are far too partial to be attributed to such cosmical phenomena. You say “you are convinced that inorganic conditions have some effect”— I am quite ready to believe it when I see any one experimental case, or such an accumulation of arguments pro, as I think can be adduced con. It is an open question, I grant, quite so.—but you must bring your case to the point. You say “you cannot see that the species has produced the same variations in all the stations” &c—how should you ever see whether or no, except you compare progress of individuals of same brood in each?. Again you ask “if variety A succeed in locality I. why should it not succeed at locality II. if it had ever been existent there”—my answer is that no locality II. is identical with a loc. I. & that Nat. Selection will act on an imperceptible difference—it searches where no faculty of man can follow. Consider again & ponder well the number of individuals of a brood that die for every one that lives, multiply these by the countless generations that it must have taken to have established that amount of change wh[ich] we call specific & then reflect that if besides all this we are to have direct effects of local conditions, which (remember) vary in kind & amount from year to year—& you will have such an accumulation of change effecting forces that there could be no such things as recognisable species & genera. Not only every place would have different varieties but every year in each place, & in the case of temperate plants grown in a hothouse, wet country plants in a dry house, &c &c &c, we should have startling changes, ever occurring.
Another objection to my line of argument is the changes wrought in bees by either feeding or heat (as the case may be).— but this again is change of individual, & is not propagated, for the Queen after all lays again males & drones, not Queens. Darwin I believe holds with you as to the influence of external conditions on the variation of the brood.16 I have however failed to be convinced by him of it, & I do not think he recognises the facts of variation to the extent I do. Indeed I think his book would have been more convincing had he treated variation somehow so as to have impressed the unaccustomed reader & thinker to regard it as the origin of species, & Nat Selection as the fixer of these. As it is, in most minds the two are confused, or Nat. Sel. is supposed to make the varieties as well as to fix them.17 At other times no one more stanchly denounces the effects of external circumstances in producing variation than Darwin does.— Darwin also believes in some reversion to type which is opposed to my view of variation.18 You may have a single character persist or reappear, but the sum of differences goes on increasing as you depart from the parent.— Variation I hold to be centrifugal;19 if it were not so how could it go on making species, which are only the preserved forms of each brood which circumstances favoured Remove the circumstances which kill the others as man does when he cultivates, (who kills those that nature would have spared), & you have what you call a variety, & fancy you made it, whereas you only prevented nature killing it.
After all Darwins axiom that man has never failed in getting varieties of any species he has fairly tried,20 is in favor of my view that the abstract principle called variation is enough with time to beget any amount of change; & by means of Nat: Selection to retain only such as may present any amount of difference. Finally I have come to look upon the law of variation as I do on gravitation: local circumstances may mask its effects, but upon itself they cannot act. The power that drives the stone to the ground is the same whether the stone permeates water or air or vacuum.—whether you let it fall straight or throw it forwards, or even upwards— So, A certain amount of centrifugal force of variation is distributed in certain proportions amongst the 12 peas in the pod; & except to arrest or retard the progress & amount of development of the individuals or their organs (I incline to think) local circumstances are powerless. Give more Nitrogen to Pea No 1. & you will have more & greener leaves; but its seeds again will not be as green as they too are not supplied with nitrogen.
I think my long letter will disgust you with asking any more questions; but I should be greatly obliged if you have time & would write me again on the subject— I know no one but yourself who is really thinking out Darwins views to any purpose in zoology I am sure that with you, as with me, the more you think, the less occasion you will see for anything but time & N.S. to effect change:— & that this view is the simplest & clearest in the present state of science, is one advantage at any rate. Indeed I think that it is in the present state of the enquiry, the legitimate position to take up; it is time enough to bother our heads with a 2d. secondary cause when there is some evidence of it, or some demand for it—at present I do not see one or other, & so I feel inclined to renounce any other for the present. It is not so very long since I thought differently & that variation was the first effect of circumstances on the individual.
We are sorry to hear of your Influenza—I hope it is gone now. We are all quite well & the children returned to school—
I hope when you next come to town you will let me know, & that we may have some more boxes of butterflies at the Linnean21 & get the many curious facts you name well impressed in the languid circulation of the Entomologist.
Ever most truly yrs | Jos D Hooker
Lighthearted thoughts on "the development of an Aristocracy" after a visit to Walcot Hall, Shropshire.
On CD’s point about the effect of changed conditions on the reproductive organs, JDH does not see why this is not "itself a variation, not necessarily induced by domestication, but accompanying some variety artificially selected".
- Letter no.
- Joseph Dalton Hooker
- Charles Robert Darwin
- Sent from
- Source of text
- DAR 101: 27–9; American Philosophical Society Library (Hooker papers, B/H76.2)
- Physical description