The Background of the Umwelt Concept: Jakob von Uexküll’s Theoretical Biology

The concept for which Uexküll is best known is his notion of the environment (Umwelt) as a species-specific subjective construction. This concept, however, takes its full meaning when situated in the context of Uexküll’s overall reflection on biology. The constitution of the perceptive and operative Umwelt is seen by Uexküll as part of a wider complex of organized morphogenetic, physiological, anatomical, and behavioural processes. This clearly emerges from the two editions of Uexküll’s Theoretische Biologie (1920; second, expanded edition 1928). Starting from these considerations, this paper aims to provide an overview of the links between Uexküll’s theoretical biology and related scholars and debates. The discussion will center on two chief issues. Firstly, the influence of other authors (Johannes Müller, Hermann von Helmholtz, Jacques Loeb) on Uexküll will be outlined. This will give us the opportunity to discuss Uexküll’s reception of Immanuel Kant’s transcendental approach; through the mediation of Helmholtz, in fact, Kant’s theory of perception assumes a great relevance for Uexküll’s physiology and theoretical biology (not by chance, the first two chapters of Theoretische Biologie are titled respectively "space" and "time). Secondly, the paper addresses Uexküll’s position in some long-term biological debates in the 19th and early 20th Centuries: the mechanist-vitalist debate; the discussion about nature and function of cellular protoplasm; the issue of teleology (in Uexküll’s terminology, Zweckmässigkeit, “purposefulness”) in biological phenomena. A final evaluation will be offered on the possibility of updating Uexküll’s theoretical biology.