Advaita means not two. The position, systematised by Shankara in the eighth century, holds that Brahman alone is real, that the individual self is not different from it, and that the world of separate things is an appearance rather than an independent reality. This gets summarised in English as the world is an illusion, and from there it is a short step to assuming Advaita teaches that nothing exists and nothing matters. That reading does not survive contact with the actual arguments.
The technical term is mithya, and it does not mean non-existent. It names something that appears, that has practical consequences, but that has no independent standing of its own. The standard example is a rope mistaken for a snake in dim light. The snake is not nothing, and the fear it produces is entirely real. What it lacks is separate existence apart from the rope. Advaita is not saying the world is absent. It is saying the world has no being of its own to stand on, which is a claim about dependence rather than about existence.
This is why Advaita never concludes that action is pointless. Shankara wrote commentaries, founded institutions, travelled continuously and argued with everyone, which would be strange behaviour for someone who thought nothing was there. The teaching targets a specific error, adhyasa, the superimposition of the seen upon the seer, and its aim is the removal of that error rather than the abolition of the world. What ends is not the appearance but the misreading of it.
Non-duality is a statement about how many realities there are, not about how much of the world you are permitted to take seriously. To see how the other Vedantic schools answered the same question differently, explore more of The Living Sanatan Timeline.
Part 32 of 100 — Series II: To the Eternal
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