I. Haeckel and His Opponents

At the beginning of the last century Jean Lamarck also maintained the view that, at a certain moment in the earth's development, a most simple organic something developed itself, by spontaneous generation, out of the mechanical, physical, and chemical processes. These simplest organisms then produced more perfect ones, and these again others more highly organised, right up to man. “One might therefore quite rightly name this part of the theory of evolution, which asserts the common origin of all plant and animal species from the simplest common root-forms, in honour of its most deserving founder, Lamarckianism” (Haeckel, Natural History of Creation). Haeckel has given in grandiose style an explanation of Lamarckianism by means of Darwinism.