dichotomy
Refers to the division of a whole into two mutually exclusive parts or categories. Used in logic, philosophy, and general contexts.
The dichotomy of good and evil is too simplistic.
It is dangerous to think about this problem in terms of a dichotomy.
Compound of 二 (two), 分 (divide), and 法 (method, law). The term is a direct translation of the Western concept of dichotomy.