From Idea to Law: Theory, Concept and Terminological Formation in Ernst Haeckel’s Works

Abstract

Since Charles Darwin (1809–1882) and Ernst Haeckel (1834–1919) published their trailblazing ideas, the scientific community’s discussion of evolutionary biology has included the topic of embryological development. The concepts of ontogeny and phylogeny, still current in contemporary biology, together with the now obsolete biogenetic law and his Gastraea theory, which trace back to Haeckel, all underwent an evolution of their own in Haeckel’s works. The record of this evolution makes clear how the features of his thinking that proved durable, such as ontogeny and phylogeny, were established as such through a difficult creative process of formation of concepts, theories, and terminology that themselves enjoyed varying fortunes. Beginning with Haeckel’s Generelle Morphologie der Organismen [General Morphology of Organisms] (1866), this paper traces aspects of the conceptual and terminological evolution that takes place both within the pages of this highly complex but seminal work and then chronologically in later works. We include the use of text data mining of his works to establish and analyse word frequency patterns. We seek to indicate here some of the challenges Haeckel faced in establishing new concepts and terminology in the General Morphology (hereafter GM), and we draw attention to his efforts in later works to extend this didactic work.