This study treats ethics as a natural science and a branch of mechanistic psychology, arguing that bodily structure and physiological processes determine moral values and conduct. It analyzes the biological meanings of good and bad, interprets right and wrong as gestural and action-pattern signs, and considers virtue, vice, and conscience—including pathological aspects—in physiological terms. The author examines tensions between freedom and obligation and proposes practical techniques for ethical adjustment, asserting that the organism's physiological well-being is the ultimate criterion of ethical value.