We introduce a two-perception probabilistic concept of adaptation (TPPCA), which accounts for fast and slow adaptation processes. The outcome of both processes depends on the perceptual difference (termed herein a quantum) of how an individual perceives his or her abilities, skills, and capacities (βv) to interact, cope, and perform a given task (δi). Thus, the adaptation process is determined by (βv – δi). Fast adaptation processes target aspects that require immediate responses while slow adaptation processes involve ongoing adaptation to long-term demands. We introduce the TPPCA in several domains of inquiry, which rely on fast adaptation processes (perceptual–cognitive–action coupling, performance routines, psychological crisis, reversal states), slow adaptation processes (i.e., career aspirations, burnout), and processes that can be either fast or slow (i.e., flow, affect and mood changes, emotion regulation).