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Gregor Mendel’s suspicious data

Howard Wainer points me to a thoughtful discussion by Moti Nissani on “Psychological, Historical, and Ethical Reflections on the Mendelian Paradox.”

The paradox, as Nissani defines it, is that Mendel’s data seem in many cases too good to be true, yet Mendel had a reputation for probity and it seems doubtful that he had a Mark-Hauser-style attitude toward reporting scientific data. Nissani writes:

Taken together, the situation seems paradoxical. On the one hand, we have evidence that “the data of most, if not all, of the experiments have been falsified so as to agree closely with Mendel’s expectations.” We also have good reasons to believe that Mendel encountered linkage but failed to report it and that he may have taken the somewhat unusual step of having his scientific records destroyed shortly after his death. On the other hand, everything else we know about him/in addition to his undisputed genius/suggests a man of unimpeachable integrity, fine observational powers, and a passion for science. In other words, Mendel was as unlikely a candidate for scientific misconduct as can be imagined.

Nissani suggests that Mendel may have known what he was doing and deliberately falsified some data to make his story more compelling:

He [Mendel] was most anxious to have his results replicated and expanded, for even self-possessed people (and he wasn’t) entertain occasional misgivings about the accuracy, originality, and significance of their work.

To achieve these goals, his work had to be understood. In comparison to his theories, of whose validity he was sure, the data were of no significance whatsoever. His task was not the one faced by the normal scientist addressing a sympathetic and competent audience, but that of a revolutionary who must break through the cognitive paradigms and social prejudices of his audience. If this larger goal could be best achieved by simplification/deliberately omitting some observations from his report and adjusting others to make them more palatable to his audience/could not such a step be justified on moral grounds?


  1. revo11 says:

    No, not in this case.

    It certainly makes sense that people who get credited for the breakthrough of an idea (e.g. in art, science, money, etc.) will disproportionately have individuals who are willing to bend the rules, because those who don’t have a tendency to get swept away by the institutional barriers to the change.

    Sometimes bending the rules is just, as in cases of civil disobedience. Sometimes, it’s just cheating. Nissani’s reasoning is the same kind of b.s. that leads to premature claims of arsenic based life by NASA and Felisa Wolfe-Simon. In Mendel’s case I think people have given him the benefit of the doubt, pinning the blame on his assistant, or perhaps being unsavvy about stopping criteria for an experiment. But if he knowingly fabricated evidence, then no, that would not be justified on moral grounds.

  2. Truman says:

    Another possibility would be one of his assistants faking the results to match his theories. Do we know if he did his own experiments?

  3. […] Greater Good Posted on August 8, 2012 by reflectionephemeral Via Andrew Gellman, Moti Nissani wonders if Mendel was fabricating data for the advancement of science: Taken […]

  4. KMC says:


    People involved in civil disobedience don’t try to convince people that they are actually following the law. On the contrary, they are purposely and openly violating the law to draw attention to their cause. Cheaters don’t want people to know they have broken the rules.

  5. Ed says:

    Taking these claims about Mendel at face value:
    I wonder what proportion of the more modern data fakers are just as convinced as Mendel was of the truth of their theory? I’d guess that this kind of reasoning might underpin a lot of fraud, so it seems like a bad policy to retrospectively excuse cases where the theory ended up useful…

  6. revo11 says:

    @kmc I agree, that (among other reasons) is why I said that breaking the rules is just in cases of civil disobedience. The two things aren’t morally equivalent, they just both happen to involve a disruption to the existing social contract (which isn’t inherently good or bad).

  7. Kjetil Halvorsen says:

    One should be carefull, so long after, saying to much in this case. Any sort of moral condemnation must use the standards of Mendel’s time, not ours, or being archaic!
    ” have taken the somewhat unusual step of having his scientific records destroyed shortly after his death ” What I have read about this, this is atyributed to the other monks, not to Mendel himself. The monks where, what to say, “uneasy” about such kind of work (involving sex!) going on in the monastery …

  8. Jeremy Fox says:

    A very thorough review in Genetics a few years ago concluded that Fisher was wrong and Mendel’s data weren’t too good to be true. Will try to find the reference when I get time…

  9. Jeremy Fox says:

    Here it is: Seems like quite a careful analysis to me, but I admit I’m not fully qualified to judge.

  10. P's in a Pod says:

    is this a new turn in this discussion or the same stuff fisher was saying? (i didn’t read the thread very carefully, so i understand that this is not the most useful way to contribute, but:) seidenfeld has written on this: