Abstract: Previous empirical and theoretical studies hold different views on the stability and variability of well-being (or subjective well-being). Set-point theory holds that well-being usually remains at a set-point, and dynamic equilibrium theory (and its variant—subjective well-being homeostasis theory) further emphasizes that well-being fluctuates in a dynamic equilibrium state within a certain set-point range. Similarly, hedonic adaptation theory considers the reasons for the stability of well-being from the perspective of emotional adaptation based on dynamic equilibrium theory. In sum, all three theories focus on how a certain equilibrium level of well-being is maintained. In contrast, sustainable happiness theory emphasizes that well-being can be improved and can undergo long-term changes. The essence of the difference between these theoretical perspectives lies in how the stability and variability of well-being are viewed. On the basis of the concepts of homeostasis and allostasis in biology and the concept of transition in physics, we believe that well-being has not only homeostasis, but also allostasis which can cause well-being homeostasis to adjust. This integrated perspective provides a new explanation framework for well-being research and has enlightening implications for the continuous improvement of well-being.

Key words: well-being, homeostasis, allostasis, transition, stability, variability