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Theoretical Biology

1920 · by Jakob von Uexküll

Applies Kant’s theory of knowledge to living beings: each organism forms its world according to its own plan, through perceptual and effector signs.

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Introduction

“Theoretical Biology” appeared in 1920 and in a revised edition in 1928; an English translation followed in 1926. In it Uexküll sought to give biology a foundation of its own, independent of physics and chemistry. Starting from Kant, he argues that space, time and qualities are formed by the subject and that every living being, with its own perceptual and effector signs, builds its own world. Organisms are not machines but follow a “plan” that coordinates the parts with the whole and the organism with its Umwelt; the “functional circle” linking perception and action is set out here systematically. The book’s anti-Darwinian and vitalist traits were rejected by most biologists, but its theory of the Umwelt was taken up by philosophers such as Heidegger, Cassirer and Merleau-Ponty.

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