Mind–body dualism
Ontological dualism makes dual commitments about the nature of existence as it relates to mind and matter, and can be divided into three different types:Substance dualism is a type of dualism most famously defended by René Descartes, which states that there are two kinds of foundation: mental and body. This philosophy states that the mental can exist outside of the body, and the body cannot think. Substance dualism is important historically for having given rise to much thought regarding the famous mind–body problem. Substance dualism is a philosophical position compatible with most theologies which claim that immortal souls occupy an independent realm of existence distinct from that of the physical world.
Dualistic cosmology
For example, Mazdaism (Mazdean Zoroastrianism) is both dualistic and monotheistic (but not monist by definition) since in that philosophy God—the Creator—is purely good, and the antithesis—which is also uncreated–is an absolute one. Zurvanism (Zurvanite Zoroastrianism), Manichaeism, and Mandaeism are representative of dualistic "and" monist philosophies since each has a supreme and transcendental First Principle from which the two equal-but-opposite entities then emanate. This is also true for the lesser-known Christian gnostic religions, such as Bogomils, Catharism, and so on. More complex forms of monist dualism also exist, for instance in Hermeticism, where "Nous" "thought"—that is described to have created man—brings forth both good and evil, dependent on interpretation, whether it receives prompting from the God or from the Demon. Duality with pluralism is considered a logical fallacy.