- the state of being dual; duality
- Philos. the theory that the world is ultimately composed of, or explicable in terms of, two basic entities, as mind and matter
- the doctrine that there are two mutually antagonistic principles in the universe, good and evil
- the doctrine that man has two natures, physical and spiritual
- The condition of being double; duality.
- Philosophy The view that the world consists of or is explicable as two fundamental entities, such as mind and matter.
- Psychology The view that mental and physical properties are fundamentally different and that neither can be explained fully in terms of the other.
- Theology a. The concept that the world is ruled by the antagonistic forces of good and evil.b. The concept that humans have two basic natures, the physical and the spiritual.
- Duality; the condition of being double.
- (philosophy) The view that the world consists of, or is explicable in terms of, two fundamental principles, such as mind and matter or good and evil.
- (theology) The belief that the world is ruled by a pair of antagonistic forces, such as good and evil; the belief that man has two basic natures, the physical and the spiritual.
- (chemistry, dated) The theory, originated by Lavoisier and developed by Berzelius, that all definite compounds are binary in their nature, and consist of two distinct constituents, themselves simple or complex, and having opposite chemical or electrical affinities.