extensionalism
nounUK /ɪkˈstɛnʃənəlɪz(ə)m/ · US /ɪkˈstɛn(t)ʃənəˌlɪzəm/
Etymology From extensional + -ism (suffix forming the names of schools of thought, systems, or theories).
1
Human sciences, Philosophy, Sciences Usually The belief in extensionality.