Kant, von Baer, and causal‐historical thinking in biology. In his Kritik der Urteilskraft Kant set forth an analysis of bio‐causality which attempted to unite the best features of teleological and mechanical frameworks of explanation. Kant's analysis suggested that related organic forms must be materially interconnected in the unity of a fundamental plan or morphotype. In the hands of Karl Ernst von Baer these suggestions led to concrete researches and groundbreaking empirical discoveries, including the discovery of the mammalian ovum. Von Baer's (...) theories of developmental types, germ layers and fundamental organs offered a precise formulation of the research program initially outlined by Immanuel Kant. Above all through the embryological method von Baer introduced the analysis of causal‐historical relations as the basic tool for biological research, the power of which he revealed in the formulation of a limited theory of evolution. (shrink)