Vedanta specifies four qualifications for a student, and viveka comes first. It is defined as discrimination between the eternal and the non-eternal, nitya and anitya, and the ordering is deliberate: the other three, dispassion, the sixfold discipline, and the desire for liberation, are all described as following from it. Without viveka the rest do not have anything to attach to, because there is no reason to want liberation from something you have not yet noticed is passing.
The faculty is analytical rather than moral. It is not the judgement that worldly things are bad; it is the observation that they do not persist, which is a different and more easily verified claim. Everything available to experience begins, changes and ends, including the states of mind that pursue it. Viveka is simply the steady application of that observation, and its usual effect is not disgust with the world but the deflation of the assumption that any particular arrangement of it will finally settle the matter.
The classical image is the swan said to separate milk from water when the two are mixed. What makes the analogy apt is that no third thing is added: the components were both already present and the capacity is one of discernment rather than transformation. Applied to experience, viveka separates what is being observed from the awareness observing it, which is the same distinction that the doctrine of adhyasa is built to explain, and once it is running, dispassion follows without needing to be manufactured.
Viveka is a faculty rather than a belief, which is why Vedanta puts it before everything else. To see the confusion it is designed to undo, explore more of The Living Sanatan Timeline.
Part 5 of 100 — Series II: To the Eternal
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