Letters to the Editor

LETTERS TO THE EDITOR Dear Sir: The story that Mendel's classic paper of1865 on genetics was lost for thirty-five years and was rediscovered bythree workers (De Vries, Correns, and Tschermak) simultaneously (1900) and independently (in Holland, Germany, and Austria) is well known [i, pp. 25-32]. I have some doubt about the likelihood ofsuch an occurrence, which seems quite improbable from a mathematical point ofview. To argue the point beyond speculation one needs some knowledge of the quantitative law of information propagation from which the mathematical probability of such an event may be estimated quantitatively. Recently, I happened to come across some information bearing on such a law from which the desired probability may be estimated. The information comes with the publication ofmy paper "Transcription ofthe DNA Molecule" (Nat. Acad. Sei. [U.S.], Proc, 58:501, 1967). The paper elicited over 1,000 requests for reprints; the number is sufficiently large to make possible a meaningful statistical analysis ofthe time lag between the publication and the recognition of a paper. Since this was the third paper ofmine for which the number ofreprint requests reached 1,000, 1 was well prepared to take the data at the earliest sign ofan avalanche. The number ofrequests received per week starting September 2, 1967 which I counted and kept for this purpose is plotted as a function oftime in figure 1. It is obvious that the decreasing of this number in the course of time may be reasonably represented by a simple exponential curve, the half-life ofwhich, as ascertained from the figure, is 5.5 weeks. A law ofexponential decay concerning information propagation is quite reasonable from theoretical ground. The deviations of the points from the line drawn are all explainable in terms of secondary complicating factors such as the lack ofsynchronization of the dis tribution of the journal, geographical dispersion, Christmas mail rush, and statistical fluctuation when the counts become small. This exponential law may be reinterpreted, as in the case of the law of radioactive decay, to mean the following: the probability of an active research worker's coming across a particular published paper decreases with time exponentially with a half-life of 5.5 weeks after publication. The validity ofthis interpretation may be argued, but in the absence ofany betterknowledge on this point this interpretation will at least give us some quantitative estimate. Accordingly, the probability ofone worker's rediscovering a paper published thirtyfiveyears ago, on purely statistical ground, is about (|)3s-s2/s-s = (|)·"?. The probability ofthree workers' rediscovering it thirty-five years later simultaneously is [(e)331]3, which is nearly (|)I0°°. This is the probability offlipping 1,000 coins with all heads up. One may 636 Letters to the Editor Perspectives in Biology and Medicine · Summer 1969 argue that the speed ofcommunication at Mendel's time was much slower than now, but even assuming a half-life ten times as long (one year), the probability would still be (^)100, the same as that offlipping ioo coins with all heads up. Ifone allows one minute to flip and count ioo coins, one has to keep on flipping for io25 years before realizing ioo heads up, a time a quadrillion times longer than the age of the present universe. Nobody believes that events with such a small probability may occur in everyday life. Thus from a mathematical point ofview the story that Mendel's paper was lost and then rediscovered thirty-five years later by three independent workers simultaneously cannot be true. What is the truth, then? The truth is that Mendel's paper was never lost in the first place; it was simply ignored. Number per week 1000 O 10ZO 30 TIME (WEEKS) Fig. i.—The number ofcards requesting reprints ofNat. Acad. Sei. (U.S.), Proc, 58:501, 1967 received per week plotted as a function oftime. Any probability higher than the statistical probability indicates the existence ofcorrelation . Correlation here means that Mendel's paper was known to the scientific community . The allegation that the paper was lost is an excuse to cover up the sinful act of deliberate or unintentional suppression ofan epoch-making discovery by unrecognized workers. Recent research has shown that Mendel made...