Professor Packard, Lamarck’s biographer, and one of his warmest admirers, at the close of his chapter devoted to the denial of “pure” Darwinism says: “We must never forget or under-estimate, however, the inestimable value of the services rendered by Darwin, who by his patience, industry, and rare genius for observation and experiment, and his powers of lucid exposition, convinced the world of the truth of evolution, with the result that it has transformed the philosophy of our day. We are all evolutionists, though we may differ as to the nature of the efficient causes.”
There are now three possible positions. (1) That of the Lamarckians, pure and simple, who maintain that Lamarck’s theory in itself explains all the phenomena, and that Darwin’s principle of selection is not only invalid but superfluous. This school is practically extinct, though Packard often sails to its very edge in his efforts to defend his subject, as is the manner of biographers. (2) The Neo- (New)- Lamarckians who develop Lamarck’s theory and add to it Darwin’s selective principle as of greater, equal, or secondary importance, according as they lean the more strongly to Darwin or Lamarck. This position held the field almost alone, until Weismann fired his opening gun in 1883. He founded (3) the Neo-Darwinian school which repudiates altogether the Lamarckian factor of the hereditary transmission of acquired characters, and maintains that Darwin’s theory is able to dispense with Lamarckian ideas of use and disuse.
As Weismann is the storm center of the controversy we will now examine his theory.
In 1883 Weismann became the pro-Rector of the University of Freiburg and in the hall of the University, in June of that year, he publicly delivered his inaugural lecture “On Heredity.” This lecture is generally regarded as the first broadside in that war which filled with its reverberations the scientific magazines of the world for the next thirteen years. As one writer aptly says, “The warring scientists splashed like irate cuttle-fishes in clouds of their own ink.” About 1896 however, the public grew tired of the never-ending flood of biological lore on what looked to the lay mind like an insoluble problem. The editors, with their fingers on the public pulse, cried, “A plague on both your houses,” and sent the savants to seek in their laboratories the victories denied to their pens.