Luiz Fernando Proença

This article presents some of the philosophical and scientific foundations of the Estonian biologist and philosopher Jakob von Uexküll (1864-1944). To this end, it is divided into five parts. The Introduction presents von Uexküll's main concept, the world-own (Umwelt). Section 1 presents Kant's transcendental aesthetics as Uexküll's main theoretical foundation; section 2 explains the school origins of Kantian influence on the Estonian biologist's background; section 3 emphasises a second aspect of Kantianism that influenced Uexküll's teleology; the last section argues that these philosophical and scientific foundations underpinned the theory of world-owns (Umweltenlehre), as named by von Uexküll.