Moral dualism is the belief of the great complement or conflict between the benevolent and the malevolent. It simply implies that there are two moral opposites at work, independent of any interpretation of what might be "moral" and independent of how these may be represented. The moral opposites might, for example, exist in a world view which has one god, more than one god, or none. 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 is destructive.

Alternatively, in ontological dualism, the world is divided into two overarching categories. The opposition and combination of the universe's two basic principles of yin and yang is a large part of Chinese philosophy, and is an important feature of Taoism, both as a philosophy and as a religion (it is also discussed in Confucianism).

In theology, dualism can refer to the relationship between God and creation. The Christian dua . . . more

https://en.wikipedia.org/wiki/Dualism