Nondualism may be viewed as the understanding or belief that dualism or dichotomy are illusory phenomena. It is accessible as a belief, theory, condition, as part of a tradition, as a practice, or as the quality of union with reality. A nondual philosophical or religious perspective or theory maintains that there is no fundamental distinction between mind and matter, or that the entire phenomenological world is an illusion
Many traditions state that the true condition or nature of reality is nondualistic, and that these dichotomies are either unreal or inaccurate conveniences. While attitudes towards the experience of duality and self may vary, nondual traditions converge on the view that the ego, or sense of personal being and control, is ultimately an illusion. As such many nondual traditions have significant overlap with mysticism.
It should be pointed out that there can be no such thing as a nondual perspective or theory or experience, only a realization of Oneness or nonduality. One cannot accurately claim to experience nonduality, because the concept of experience depends on the subject-object distinction, which is a duality. The subject experiences an object, which is something separate from the subject. This is incompatible with a truly nondual realization. Thus there cannot truly be an accurate verbal account of this union, only words that insufficiently point to the realization.
All schools of Buddhism teach “no-self”, or pali anatta. It is the non-duality of subject and object, which is very explicitly stated by the Buddha in verses such as “In seeing, there is just seeing. No seer and nothing seen. In hearing, there is just hearing. No hearer and nothing heard.”
Dzogchen is a relatively esoteric tradition concerned with the natural state, emphasizing direct experience. The Dzogchen practitioner realizes that appearance and emptiness are inseparable. One must transcend dualistic thoughts to perceive the true nature of one’s pure mind. This primordial nature is clear light, unproduced and unchanging, free from all defilements. One’s ordinary mind is caught up in dualistic conceptions, but the pure mind is unafflicted by delusions.
Through meditation, the Dzogchen practitioner experiences that thoughts have no substance. Mental phenomena arise and fall in the mind, but fundamentally they are empty. The practitioner then considers where the mind itself resides. The mind can not exist in the ever changing external phenomena and through careful examination one realizes that the mind is emptiness. All dualistic conceptions disappear with this understanding.
Zen is a non dual tradition. It can be considered a religion, a philosophy, or simply a practice depending on one’s perspective. It has also been described as a way of life, work, and an art form. Zen practitioners deny the usefulness of such labels, calling them, “The finger pointing at the moon.”
Sikhism is a monotheistic religion which hold the view of non dualism. A principle cause of suffering in Sikhism is the ego, the delusion of identifying oneself as an individual separate from the surroundings. From the ego arises the desires, pride, emotional attachments, anger, lust, etc., thus putting humans on the path of destruction. According to Sikhism the true nature of all humans is the same as God and everything that originates with God. The goal of a Sikh is to conquer the ego and realize true nature or self, which is the same as God’s.