William Blake, The Good and Evil Angels Struggling for the Possession of a Child, 1795.
Despite the efforts of various scholars down through the ages endeavouring to provide a tradition for dualist renditions of the universe, the particular emanations of dualist thought still remain aloof to biased revisions and broad generalisations that either celebrate or condemn. Although the term ‘dualism’ denotes the existence of the state of two parts in the form of binary opposition, the manner in which this idea finds expression differentiates itself to the extent of both embracing opposing doctrines and transcending them. The reason for this is due to the fact that dualism has a different application in philosophical, historical, and cosmological contexts. The term ‘dualism’, as a distinct area of description for the religious tradition of Manichaeism, was introduced by Thomas Hyde in 1700 and then further introduced by Christian Wolff to define philosophical systems that relate to the mind and body as two distinct entities. However, the use of the term ‘dualism’ in philosophical discourse differs greatly from its examination within a religious context with cosmological and historical references. Although many have argued that dualism within a religious context is the rite of passage from polytheism to monotheism, or a rebellious outcry against monotheistic cosmology, studies in individual religious traditions that have and continue to express dualist tendencies demonstrate that these tendencies exist in polytheistic, monotheistic, and monistic religious traditions, either as metaphysical expressions on the margins or inherent doctrines within the core structure of the religious tradition.
The essence of religious dualism usually manifests in the cosmic battle between the forces of good and light against the minions of evil and darkness, which exists as an all-embracing conflict defining arcane mechanisms of the universe. In some traditions, such as Zoroastrianism and Manichaeism, this cosmic struggle is between two distinct and coeternal principles, and the battle is everlasting, for it is the very definition of the universe itself. In more moderate dualistic traditions, such the Gnostic school of Valentinianism, the source of evil and darkness is inferior to the principle of good and light, with the former being an extension of the latter. Some dualist traditions have an eschatological dimension, where at the end of time a purification of the world will take place and all evil will be vanquished. A final difference that takes place between various dualist religious schools is the way in which creation is conceived. In cosmic dualism, such as Zoroastrianism, the created world is not conceived as evil, but instead as a creation of the good principle that has been assaulted by the forces of evil and darkness. However, in more anti-cosmic dualist systems, as presented in the mythologies of some Gnostic schools, the created world is seen as a creation of the Demiurge who opposes the good and light principle that resides within the domain of spirit.
In relation to the diverse types of dualism that can be found in polytheistic, monotheistic and monistic religious traditions, Stoyanov writes,
In certain religious traditions diverse types of dualism could coalesce and appear in torturous combinations with monotheistic and polytheistic conceptions. What is more, within the framework of the development of some religious traditions, there can be detected a transition from dualist tendencies or notions of duality to the dualism of the irreconcilable cosmic opposites or a reversal of this process – a neutralization of the dualist elements implicit or developed in earlier stages of religion.