ultimate cause
Technical term in philosophy and biology, contrasted with 至近要因 (proximate cause). Refers to the fundamental, often evolutionary or deep-seated reason behind a phenomenon.
See also: 至近要因
In biology, a distinction is made between the ultimate cause and the proximate cause of a behavior.
The philosopher sought the ultimate cause of human happiness.
Proximate cause; the immediate mechanism or trigger, as opposed to the deeper evolutionary or fundamental reason (究極要因).
Compound of 究極 (ultimate) and 要因 (cause, factor). The term is a calque from English 'ultimate cause', used in academic contexts.