The Evolution of the idea of homeostasis: Determinism, stochastics, and chaos–self-organization

Homeostasis is a basic concept in investigating all living systems. Homeostasis and life are synonyms to a certain extent. The concept of homeostasis has been studied and developed for more than 150 years; however, only the 21st century brought us close to understanding homeostasis as a state of a biosystem and a continuous process. The chaos and self-organization theory (CSOT) proves that the conventional views based on determinism (functional analysis) or stochastics (when stochastic uncertainty or certainty occurs) cannot describe homeostasis as defined by W.B. Cannon and his followers. The new CSOT shows a clear boundary between determinism, stochastics (and deterministic chaos), and third-type systems, which have five special properties (principles of self-organization) and can be described in terms of quasiattractors. Kinematics is understood as the motion of quasi-attractors in the phase spaces of states. Complexity is introduced as the rate of evolution of complex biological systems, differing from the definition by Prigogine–Glansdorff. At the same time, concepts of uncertainty of the first and second types and an analog of the Heisenberg calculus are introduced for complexity. According to these concepts, complex biosystems are transferred from the area of traditional science to a new area of the theory of chaos and self-organization.