Alkaline Recapitulation: Haeckel’s Hypothesis and the Afterlife of a Concept

T he german naturalist ernst haeckel began many of his works of popular science with a rhetorical trope that was unusual amid the positivism of the late nineteenth century.1 In the two central books of his career, his Natural History of Creation and his Evolution of Man, volumes bookended by the ultratechnical General Morphology and the ultrapopular Riddle of the Universe, Haeckel opened his account with a historical recapitulation of previous attempts to understand the scientific phenomenon in question.2 In both cases he emphasized the perennial nature of the problem and how it had exercised the minds of generations of thinkers. More important, however, was Haeckel’s desire to advance two positions that seemed to him perfectly consonant with one another. On the one hand, there was his conviction that the “simple idea” of Darwinian theory, “that the Struggle for Existence in Nature evolves new Species without design, just as the Will of Man produces new Varieties in cultivation with design,” 3 did not come out of nowhere but was in many respects anticipated by Goethe, Oken, and Lamarck,