I. Haeckel and His Opponents

To-day we look back upon forty years of scientific development, which stand under the influence of Charles Darwin's line of thought. Rightly could Ernst Haeckel say in his book, On our Present Knowledge of Man's Origin, which reproduces an address delivered by him at the Fourth International Congress of Zoologists in Cambridge on 26th August, 1898: “Forty years of Darwinism! What a huge progress in our knowledge of Nature! And what a revolution in our weightiest views, not only in the more closely affected departments, but also in that of anthropology, and equally in all the so-called psychological sciences.”