Claims

The body can be understood as an 'IF THEN' system with triggers that activate specific physiological processes, and most physiological expressions cannot be induced by willpower alone—the relevant triggers must be present.

The stress response system (fight-or-flight) is originally adaptive: when encountering a threat like a tiger, the pituitary gland secretes adrenocorticotropic hormone, cortisol is released, heart rate increases, digestion turns off, and the organism mobilizes for physical exertion.