Umwelt

[1] In the semiotic theories of Jakob von Uexküll and Thomas Sebeok, it is considered to be the "biological foundations that lie at the very center of the study of both communication and signification in the human [and non-human] animal".

The biosemiotic turn in Jakob von Uexküll's analysis occurs in his discussion of the animal's relationship with its environment.

The umwelt is for him an environment-world which is, according to Agamben, "constituted by a more or less broad series of elements [called] 'carriers of significance' or 'marks' which are the only things that interest the animal".

Agamben goes on to paraphrase Uexküll's example of the tick, saying: "...this eyeless animal finds the way to her watchpoint [at the top of a tall blade of grass] with the help of only its skin’s general sensitivity to light.

The odor of butyric acid, which emanates from the sebaceous follicles of all mammals, works on the tick as a signal that causes her to abandon her post (on top of the blade of grass/bush) and fall blindly downward toward her prey.

In "Welt und Umwelt"[9] and "Die Wahrheit der Dinge", the philosopher and sociologist Josef Pieper argued that reason allows the human person to live in "Welt" (world) while plants and animals do indeed live in an Umwelt—a notion he traces back far beyond Uexküll to Plato, Aristotle, and Thomas Aquinas.