The German Genius
what exactly these were. 24
Back in Brno, Mendel was elected abbot in 1868, and he too used his time to promote farming. In 1877 he helped introduce weather forecasts for farmers in Moravia, the first in central Europe. 25
More to the point, he began experimenting with peas. The results for which we remember him were the fruit of ten years of “tedious experiments” in plant growing and crossing, seed gathering, careful labeling, sorting, and counting. Almost 30,000 plants were involved. As the Dictionary of Scientific Biography notes, “It is hardly conceivable that it could have been accomplished without a precise plan and a preconceived idea of the results to be expected.” In other words, his experiments were designed to test a specific hypothesis.
From 1856 to 1863 Mendel cultivated seven pairs of characteristics, suspecting that heredity “is particulate,” contrary to the ideas of “blending inheritance” to which many others subscribed. He observed that, with seven pairs of characteristics, in the first generation all hybrids are alike—and the parental characteristics (e.g., round seed shape) are unchanged. This characteristic he called “dominant.” The other characteristic (e.g., angular shape), which only appears in the next generation, he called “recessive.” What he called “elements” determine each paired character and pass in the germ cells of the hybrids, without influencing each other . In hybrid progeny both parental forms appear again and this, he realized, could be represented mathematically/statistically with A denoting dominant round seed shape, and a denoting the recessive angular shape. Were they to meet at random, he said, the resulting combination would be:
¼ AA + ¼ Aa + ¼ aA + ¼ aa
After 1900, this was known as Mendel’s law (or principle) of segregation and can be simplified mathematically as:
A + 2 Aa + a
He also observed that with seven alternative characteristics, 128 associations were found—in other words, 2 7 . He therefore concluded that the “behaviour of each of different traits in a hybrid association is independent of all other differences in the two parental plants.” This principle was later called Mendel’s law of independent assortment. 26
Mendel’s employment of large populations of plants was new, and it was this that enabled him to extract “laws” from otherwise random behavior—statistics had come of age in biology. 27 He attempted to sum up the significance of his work in Versuche über Pflanzenhybriden (1866). This memoir, his magnum opus and one of the most important papers in the history of biology, was the foundation of genetic studies. It was never truly appreciated because he had difficulty following up his pea work, his experiments with bees failing because of the complex problems involved in the controled mating of queen bees. He did show that hybrids of Mattiola , Zea , and Mirabilis “behave exactly like those of Pisum ” but colleagues like Nägeli, to whom he wrote a series of letters, remained doubtful. 28
Mendel had read On the Origin of Species . A copy of the German translation, with Mendel’s marginalia, is preserved in the Mendelianum in Brno. These marginalia show his readiness to accept the theory of natural selection. Darwin, however, never seems to have grasped that hybridization provided an explanation as to the causes of variation. As a result, Mendel died a lonely unrecognized genius.
T HE I NVENTION OF THE U NCONSCIOUS
Just as some form of “evolution” was in the minds of many biologists and philosophers in Germany (and elsewhere) from the late eighteenth century on, so too the idea of the unconscious was a long time germinating. “Spirit release” rituals were common in Asia Minor as early as 1000 B.C. 29
Among the general background factors giving rise to the unconscious, Romanticism was intimately involved, says Henri Ellenberger in his magisterial The Discovery of the Unconscious . This was because Romantic philosophy embraced the notion of Urphänomene , “primordial phenomena” and the metamorphoses deriving from them. Among the Urphänomene were the Urpflanze , the primordial plant, the Allsinn , the universal sense, and the unconscious. Johann Christian August Heinroth (1773–1843), described by Ellenberger as a “romantic doctor,” argued that conscience originated in another primordial phenomenon, the Über-Uns (over-us).
A number of
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