noun
A technical term in philosophy, psychology, and sociology referring to the theory that mind and body, or individuals and society, interact and influence each other.
相互作用説は、心と体が互いに影響し合うという考え方だ。
Interactionism is the idea that mind and body influence each other.
Compound of 相互 (sōgo, 'mutual') + 作用 (sayō, 'action') + 説 (setsu, 'theory'). A calque from English 'interactionism'.