Dualism (from the Latin word duo meaning "two")[1] denotes the state of two parts. The term dualism was originally coined to denote co-eternal[clarification needed] binary opposition, a meaning that is preserved in metaphysical and philosophicalduality discourse but has been more generalized in other usages to indicate a system which contains two essential parts.

Moral dualism began as a theological belief. Dualism was first seen implicitly in Egyptian Religious beliefs by the contrast of the gods Set (disorder, death) and Osiris (order, life).[2] The first explicit conception of dualism came from the Ancient Persian Religion of Zoroastrianism around the mid-fifth century BC.