In hierarchical thermodynamics, a thermostat is a part of the total system that can be considered as the surroundings or environment. [1] The thermostat imposes certain conditions on the system under study, which is a subsystem. These conditions can be constant temperature, pressure, chemical potentials, or any other potentials, e.g. sociological ones, etc. [2] The application of the terminology of thermostat in human social settings leads to the analysis of energetic boundary analysis, such as territories, or social boundaries, etc. and the free energy coupling conditions necessary to cross one. [3]

References
1. (a) Gladyshev, Georgi, P. (1997). Thermodynamic Theory of the Evolution of Living Beings. Commack, New York: Nova Science Publishers.
(b) Kubo, R. (1968). Thermodynamics. Amsterdam: North-Holland Publishing Co.
2. Gladyshev, Georgi, P. (1997). Thermodynamic Theory of the Evolution of Living Beings (Appendix 2: "thermostat"). Nova Science Publishers.
3. Thims, Libb. (2007). Human Chemistry (Volume One), (preview). Morrisville, NC: LuLu.