Classical commentary does not present its conclusions flat. It stages a debate: a position is raised, developed in its strongest form, examined, and answered. Only then does the commentary state where it stands. Two Sanskrit terms mark the rhythm of that debate everywhere in the Atlas.
Pūrvapakṣa
A pūrvapakṣa is a position the commentator sets out in order to examine it: an objection, a rival school’s reading, or an interpretation being tested. Commentators often develop these positions at length and in their strongest form, so a pūrvapakṣa can sound exactly like the author speaking in his own voice. It is not, or not yet: it is one side of a debate the commentary is staging on the page. Treat the label as marking a role in the argument, not a verdict on everything said within it. A pūrvapakṣa is not simply “the wrong view”; a point raised there may be perfectly sound, and may even be affirmed later while the way it was argued is set aside. What the label tells you is only this: do not assume this passage is the commentator’s final position.
Siddhānta
A siddhānta is the settled position the commentator affirms at this point in the argument, usually after one or more opposing positions have been raised and examined. It is the voice of the commentary’s own teaching in that context: the place where the staged debate comes to rest. Two cautions keep the term honest. A siddhānta is the conclusion of this argument, at this place in the text; a commentator may take up the same question again elsewhere. And it is the conclusion of this commentator: at the very same sūtra, different traditions may each reach their own siddhānta, and they may disagree. That disagreement is what Compare exists to show.
Exposition and opponent’s view
Two further labels appear occasionally. Exposition marks the explanatory voice: passages that simply unpack a word, supply context, or walk through what the sūtra says, without being a move in a debate. Opponent’s view marks a rarer case, where a commentator names a rival tradition’s tenet only to note and dismiss it in passing, without developing it as a real pūrvapakṣa.
In Concepts, every quoted passage carries its label. Tap a pūrvapakṣa or siddhānta label anywhere in the Atlas to see its definition without losing your place.