Homeostasis
My hypothesis is as follows: if being is dwelling, then that should be said not only for humans but also for all living beings.Roland Schaer, Répondre du vivant (Paris: Éd. Le Pommier, 2013). This hypothesis seems to me to have been both suggested and rejected by Heidegger. Suggested in the reference to physis and rejected with the exclusion of non-humans and non-parents. To understand this, I refer to what life sciences call “homeostasis.”
Claude Bernard introduced the concept of an “interior milieu.” He points out that there are categories of beings whose life patterns change with the fluctuations of the environment; thereby, during the winter, seeds enter a period of dormancy that does not stop until climatic conditions that are favorable to germination return; similarly, marmots hibernate, go into inactivity until warm weather returns. The “most highly organized animals” according to Claude Bernard are those that manage to free themselves from this dependence on the fluctuations of the external environment because their life takes place in a second milieu, a milieu within the milieu. That is what he calls the “interior milieu,” a milieu produced by the body to provide dwelling to its components. It is a self-regulated and relatively stable environment, whose parameters are kept more or less constant. Among homeothermic animals such as us, cells, tissues, and organs maintain a constant temperature, in both summer and winter. This is what we now call “homeostasis:” chemical stability, “climatic” stability, storing reserves that reduce the dependence on the variation of resources in the external environment, and so on.
On this point, with the Neolithic Revolution, along with the invention and the expansion of agriculture, animal husbandry, and sedentarization, humans have in a sense produced a homeostasis on the “outside.” Nomadic hunter-gatherers need to move according to the availability of resources, either when they deplete or when seasons force them to look for more hospitable regions, just as migratory birds do; they have to change environments. With agriculture and animal husbandry, by “domesticating” plant and animal resources, by keeping them at home and storing them, humans in the Neolithic period freed themselves from the fluctuations to some extent; they changed their milieu, they built a milieu of greater homeostasis, a more livable outside that had become their home somewhere on Earth. What is more, this was a multi-specific dwelling given that plants and plants were welcomed “into their home,” as domesticated beings.
I believe that the invention of homeostasis, the invention of the interior milieu, is the invention of a form of dwelling, an invention of evolution. With it, the living, before even transforming its milieu to make it more or less inhabitable, makes itself an interior milieu for its components and thus makes itself dwelling.
Let us come back to the question of the enclosure. If we are to say that the exterior milieu that is a dwelling, then an organism or a population of organisms must then constantly exchange matter, energy, and information with it. Metabolism is key to its survival; this circulation, this exchange, is why the living survives in its condition of a living thing, that it continues being by self-renewing; if the exchange stops, the living thing dies. Though for the living, being is dwelling, this cannot mean “being enclosed.” Furthermore, to return to the production of homeostasis, that I view as being the production of dwelling, not only must this process take place while constantly exchanging with the external environment—while preserving the porosity of the membrane, while keeping the system open under pain of death—but the fluctuations of the external environment themselves serve as a pool of information and are used to regulate the interior milieu and maintain its stability by means of negative feedback loops. Here again, the living defends its exterior by establishing a sort of connivance with it, thereby limiting its own vulnerability. There is no dwelling that is not an open territory; an enclosure means death. An impregnable fortress is a tomb. Any dwelling is an exchanger.