a belief in two gods, especially as independent and opposed principles of good and evil.
The belief in two antagonistic deities, one a force for good, one for evil.
By contrast, ditheism or bitheism implies (at least) two gods. While bitheism implies harmony, ditheism implies rivalry and opposition, such as between good and evil, or bright and dark, or summer and winter. For example, a ditheistic system would be one in which one god is creative, the other destructive. (Source- Wikipedia)
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