Duality manifests, arises, appears in advaita, non-duality. It is an apparent reality within unity. The non-dual (advaita) reality-truth is the basis of duality.

There are different forms of duality. In the first place to show that all objects and thoughts in the world of phenomena have an opposite. Pole and opposite dissolve each other and arrive at zero on balance and by definition.

In addition, duality expresses the plurality (nānā) of all phenomena and differences.

But in teaching, duality has a special function. It is a phase in the teaching, as it were. The invitation is to distinguish that which is always (nitya) from that which is temporary and impermanent (anitya). This is an important qualification for freedom. When this is understood, it is taught that anitya is nothing but nitya (advaita, non-dual). In this way we learn how to arrive at advaita through dvaita.

Duality doesn’t have to be a problem if you understand that every part in the story has its opposite, because the whole logically ends up at zero. When you see this, you live in objective detachment (dispassion, vairagya), another important qualification for vedānta. The whole of the physical universe (think of celestial bodies and black holes), but also the whole in a lifetime. The body is born and the body dies. If I satisfy a desire, there will be a counter-effect that I suffer from, usually attachment and fear of losing something. This insight is beneficial and absolutely necessary to be free. Only when I no longer have to strive in duality am I fit for truth.

The duality of objects, including experiences, simply appears. It is advisable to see it as a game, entertainment, a story. To consider the appearance of life in the world with a mind and a body as real (when in fact it is mithyā) is a problem. Trying to win over and over again against a system that has its flawless laws is clumsy and stupid. This maintains saṁsāra, the wheel of urge, desire, and action, or the wheel of birth, decline, and rebirth.

Understanding how duality works, therefore, really gives the inner peace that everyone is looking for. It is that urge, inferiority, and frustration that bothers us so much.

Duality and non-duality are therefore not opposites. Non-duality is simply the truth of apparent duality. They don’t bite each other. They don’t even have anything to do with each other, because they are two completely different realities. Non-duality is the infinite truth, existence itself, free, full, and very shining as consciousness. That’s me. Duality is only a phenomenon in it. It is relatively true (mithyā) and therefore dependent on satya for its existence, impermanent and changeable.

For the one who is free, the momentum of prārabdha karma, (the karma that has already been carefully begun and will be precisely settled and unfolded), will play out. This seems dual, but is not experienced as such by the free jñānī (knower, connoisseur).