Jakob von Uexküll’s take on the concept of Umwelt was never completely stable, it had to endure multiple transformations: in its early stages it was presented as an equivalent of the French voice Milieu, then a perception-shaped image of the world of action that every animal possesses and, at the zenith of its meaning a co-constituted unity of relationships that shape the very experience of life. Nevertheless, there was one aspect of the Umweltlehre that retained its first conceived conviction: the anti-reductionist battling idea that a natural being, that is, a subject, cannot be assumed as a partes extra partes ensembled machine that operates in an all static purely physicochemical external world. Its our aim to present the uexküllian vision of subjects that proposed that the way of existing of natural beings was to be conceived as a whole unity that shaped differently from a machine; in it, not only a methodological distinction was made, but an ontological one that propelled organisms as a complex relational form of being that distinguished the non-natural from the natural. Thus, both subject and world find a relational structure that binds them together in a co-constituted natural historical process that conceives the world as a meaning-making system arising from the interaction of different biological subjects as in an all-encompassing melody singing itself.