Non-Duality is the term for a view of the world as not two, nor one but undivided  and without a second—not the duality of a person and the world outside him or her, but instead a totality which is wholly subjective. Oneness, or unity, itself implies something outside, which is not the case and why those terms are not used instead. If there is one, there must be another. But with non-duality there is no second. The view derives from Eastern belief, principally Hindu advaita, which literally means without duality. It also finds support in Buddhism (Zen, for example, where form is emptiness and emptiness form as stated in the Heart Sutra).

A central tenet of non-duality is that self—that which we call our self—does not exist. The evidence is offered by a methodology.
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