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The Francis Crick Papers

Letter from Ernst Mayr to Francis Crick pdf (308,672 Bytes) transcript of pdf
Letter from Ernst Mayr to Francis Crick
In his letter the evolutionary biologist Ernst Mayr commented on the contemporary debate in the United States about the role of genetics, race, and environment in human behavior. The debate was triggered by comments made by the Nobel Prize winning physicist William Shockley that the lag in educational achievements of black Americans could be accounted for by inherited racial traits, namely a lower IQ. Mayr rejected Shockley's thesis as racist and simplistic, calling instead for a research program in "positive eugenics," the idea of increasing the frequency of desirable traits by encouraging reproduction by individuals with these traits.
Number of Image Pages:
3 (308,672 Bytes)
1971-04-14 (April 14, 1971)
Mayr, Ernst
Crick, Francis
Original Repository: Wellcome Library for the History and Understanding of Medicine. Francis Harry Compton Crick Papers
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Reproduced with permission of Ernst Mayr.
Medical Subject Headings (MeSH):
Continental Population Groups
Exhibit Category:
Embryology and the Organization of DNA in Higher Organisms, 1966-1976
Metadata Record Letter from Francis Crick to Ernst Mayr (April 21, 1971) pdf (69,832 Bytes) transcript of pdf
Box Number: 12
Folder Number: PP/CRI/D/1/2/8
Unique Identifier:
Document Type:
Letters (correspondence)
Physical Condition:
Series: Correspondence
SubSeries: Alphabetical Correspondence
SubSubSeries: Correspondence 2
Folder: Correspondence: M
April 14, 1971
Dear Francis:
John Edsall has made available to me copies of his correspondence with you. Let me begin by saying that I fully support what he writes in his letter of March 5. One must understand our letter to Shockley on the basis of the preceding history. Fellow members of the Academy had strongly urged the Council of the Academy to come out with a report favoring accelerated research in the area of human abilities. These endeavors were virtually shipwrecked when Shockley came out with his racist formulations. Perhaps you in Great Britain do not fully understand how important it is in a racially mixed nation to deal with the merits of individuals and not typologically with mean values of races, considering that there are so many people who lack the biological understanding to appreciate that every individual is genetically unique and that curves of variation of individual characters overlap widely between representatives of different races.
I admit that the letter published by us is unbalanced by not including a constructive statement about the need for increased research in this area. Indeed, I had refused to sign an early version; I signed the letter only after the last paragraph was added, which to me is the most important one because it states clearly that no individual should be judged merely by his membership in a given race. But this is precisely what Shockley is doing and this is what is called racism. It is most important to get rid of this attitude before we can have any hope for a constructive program of research and action in positive eugenics.
John has already pointed out that there is nothing in our statement that reflects adversely on Jensen and his report. In a class I gave last year we devoted two hours to Jensen's report, largely favorably, I might say, pointing out, however, how difficult it is to eliminate entirely the environmental factor.
I have been favoring positive eugenics as far back as I can remember. As I get older, I find the objective as important as ever, but I appreciate also increasingly how difficult it is to achieve this goal, particularly in a democratic western society. Even if we could solve all the biological problems, and they are formidable, there still remains the problem of coping with the demand for "freedom of reproduction," a freedom which fortunately will have to be abolished anyhow if we are not drown in human bodies. The time will come, and perhaps sooner than we think, when parents will have to take out a license to produce a child. No one seems to question that it requires a license for such a harmless activity as driving a car, and yet such an important activity as influencing the gene pool of the next generation can be carried out unlicensed. A biologist will understand the logic of this argument, but how many non-biologists would? Obviously, then, we need massive education. Such education is going to be paralyzed at the very start if it gets mixed up with racist and anti-racist arguments. This is why the Academy has to disassociate itself from Shockley's arguments. I have heard him argue by the hour, and it is very obvious that he treats human beings like so many sodium atoms or pi mesons. Population differences for him are real, the differences between individuals, however, are errors of sampling that can be ignored by focusing on mean values. I will not claim that Shockley does not somewhere know that his approach is wrong, because he must realize that even differences between individuals have a significant genetic basis. What is crucial, however, is that he seems to ignore these individual differences in his conclusions and generalizations.
Now as to positive action! The most important thing at this time is to stop talking about "The White" and "The Black." As long as we use this language, we will produce only heat but no light. We must think in terms of adopting a strategy that will permit meaningful research without offending people's sensitivities and without coming too aggressively in conflict with popular prejudices. Please do not forget that thinking in anthropology in this country was shaped by Boas (and his various disciples) and in psychology by the behaviorist school. Both schools magnify the importance of the environment and hardly mention or even deny the role of inheritance. The American school of psychoanalysis, likewise, denied any importance of inheritance, even in such clearly genetic conditions as schizophrenia. This must be kept in mind when one is thinking about strategies to be adopted for the initiation of meaningful eugenic research. A bull-in-the-china-shop attitude, like that of Shockley, will result only in the erection of impassable roadblocks. What is equally deplorable is the action of certain geneticists who imply, by overemphasizing the environmental uncertainties, that the genetic factors can be ignored as far as human abilities are concerned. But this is not the place to discuss this any further.
I have been told that highly significant work is being carried out in Israel in a comparison of the I.Q. of Polish and Yemenite Jewish children raised in the same kibbutzin. If correct and reliable, the findings would certainly strengthen the environmentalist argument.
If I may summarize my own viewpoint, it is that positive eugenics is of great importance for the future of mankind and that all roadblocks must be removed that stand in the way of intensifying research in this area. Shockley with his racist views is unfortunately the worst roadblock at this time, at least in this country; hence, his sharp rejection by some of us who are very much in favor of positive eugenics.
I do hope I have been able to shed light on our side of the argument.
Sincerely yours,
Ernst Mayr
P.S. Let me repeat once more that John Edsall has dealt so well with other aspects of Shockley's proposals that I could afford, in my letter to you, to concentrate on just one or two points. Others I have stated in my Animal Species (1963) on pp. 658-662 (largely reiterated in my new Populations, Species, and Evolution).
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