The ego and self are both self-reflexive and dualistic modes of psychological functioning based on the subtle process of mental discriminating judgment, a process that is inherently built into the structure of the psyche.
By the In-Betweener's own admission, he represents duality itself, specifically in respect to concepts such as good and evil; reason and emotion; truth and illusion; and life and death.
To the thirteenth edition of the Joel Feinberg- and Russ Shafer-Landau-edited Reason & Responsibility, Gertler contributed a paper in support of dualism.
Hegeler rejected dualism as an unscientific and untenable view and accepted monism upon the basis of exact science, and for the discussion of the more recondite and heavier problems of science and religion he founded a quarterly, The Monist, in October 1890.
In essence, the philosophy of Achintya bheda abheda, or "inconceivable oneness and difference", avoids the extremes of Shankara's monistic Advaita vedanta and Madhva's pure dualism (Dvaita) by interpreting the material and spiritual potencies of the Supreme Person (Bhagavan) as being simultaneously one and different with Him.
Only a minority of Cathars held that The Evil God (or principle) was as powerful as The Good God (also called a principle) as Mani did, a belief also known as absolute dualism.
He characterizes it as “an effort to reconcile inner duality, transcend typical masculine ideals and yield to new realities that require constant compromise and change.”