Publications

In the frst half of the twentieth century the harshest critics of Hans Driesch’s vitalistic theory depicted it as an animistic view driven by metaphysical moods, while others merely saw it as a barren hypothesis. In the last decades the heuristic value of vitalistic principles was nevertheless suggested. In this chapter I examine the epistemic role of Driesch’s critical vitalism in the progress of embryology. I frst show that it did not contribute to falsify mechanical explanations of development such as Wilhelm Roux’s mosaic theory and Driesch’s own embryonic induction model. However, Driesch’s argumentation for vitalism led to the fnal formulation of the most challenging developmental explanandum of the twentieth century: the harmonious-equipotential system (HES). I point out how major explanans like Charles M. Child’s metabolic gradients, Hans Spemann’s induction felds and Lewis Wolpert’s positional information were conceived as promising answers to Driesch’s problem