Buddhism is about Solving a Problem (from Taking Conventional Truth Seriously, by Jay L. Garfield, in Moonshadows – Conventional Truth in Buddhist Philosophy, by The Cowherds, Oxford 2011)

Buddhism is about solving a problem – the problem of the omnipresence of suffering – and the central intuition of Buddhism is that the solution to that problem is the extirpation of ignorance. Epistemology is located at the foundation of morality and gets its point just from that location. The mechanism of the extirpation of ignorance is the competent use of our authorative epistemic instruments. What that use delivers is hence, at least indirectly, always of soteriological significance – always instrumental to liberation. Inasmuch as that is the central moral virtue, and inasmuch as epistemology is so tightly bound to the soteriological project, it is also the central epistemic virtue, and what we call the goal of epistemic activity is truth. Conventional truth is hence no to truth as blunderbusses are to buses or as fake guns are to real guns but rather is simply one kind of truth.

One of the Buddha’s deepest insights was that there are two truths and that they are very different from one another. They are the objects of different kinds of cognition, and they reflect different aspects of reality. They are apprehended at different stages of practice. Despite the importance of the apprehension of ultimate truth, one can’t skip the conventional. Despite the soteriological efficacy of ultimate truth, even after Buddhahood, omniscience and compassion require the apprehension of the conventional.

Nagarjuna’s deepest insight was that, despite the vast difference between the two truths in one sense, they are, in an equally important sense, identical. We can now make better sense of that identity and of why the fact of their identityis the same fact as that of their difference. Ultimate reality is, as we know, emptiness. Emptiness is the emptiness not of existence but of intrinsic existence. To be empty of intrinsic existence is to exist only conventionally, only as the object of conventional truth. The ultimate truth about any phenomenon, on this analysis, is hence that it is merely a conventional truth. Ontologically therefore, the two truths are absolutely identical. This is the content of the idea that the two truths have a single basis: That basis is empty phenomena.Their emptiness is their conventional reality; their conventional reality is their emptiness.

Nonetheless, to know phenomena conventionally is not to know them ultimately. As objects of knowledge – that is, as intentional contents of thought, as opposed to mere phenomena – they are objects of different kinds of knowledge despite the identity at a deeper level of those objects. Hence the difference. But the respect in which they are different and that in which they are identical are, despite their difference, also identical. A mirage is deceptive because it is a refraction pattern, and it is the nature of a refraction pattern to be visually deceptive. The conventional truth is merely deceptive and conventional because, upon ultimate analysis, it fails to exist as it appears – that is, because it is ultimately empty. It is the nature of the conventional to deceive. Ultimately, since all phenomena, even ultimate truth, exist only conventionally, conventional truth is all the truth there is, and that is an ultimate and therefore a conventional truth. To fail to take conventional truth seriously as truth is therefore not only to deprecate the conventional in favor of the ultimate but also the deprecate truth per se. That way lies suffering.