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.
Nondualism
The Asian idea of nondualism developed in the Vedic and post-Vedic Hindu philosophies, as well as in the Buddhist traditions. The oldest traces of nondualism in Indian thought are found as "Advaita" in the earlier Hindu Upanishads such as Brihadaranyaka Upanishad, as well as other pre-Buddhist Upanishads such as the Chandogya Upanishad, which emphasizes the unity of individual soul called Atman and the Supreme called Brahman. In Hinduism, nondualism has more commonly become associated with the Advaita Vedanta tradition of Adi Shankara.