Nagarjuna is surely one of the most difficult philosophers to interpret in any tradition. His texts are terse and cryptic. He does not shy away from paradox or apparent contradiction. He is coy about identifying his opponents. The commentarial traditions grounded in his texts present a plethora of interpretations of his view. Nonetheless, his influence in the Mahayana Buddhist world is not only unparalleled in that tradition, but exceeds in that tradition the influence of any single Western philosopher in the West. The degree to which he is taken seriously by so many eminent Indian, Chinese, Tibetan, Korean, Japanese and Vietnamese philosophers, and lately by so many Western philosophers, alone justifies attention to his corpus. Even were he not such a titanic figure historically, the depth and beauty of his thought and the austere beauty of his philosophical poetry would justify that attention. While Nagarjuna may perplex and often infuriate, and while his texts may initially defy exegesis, anyone who spends any time with Nagarjuna's thought inevitably develops a deep respect for this master philosopher.
One of the reasons Nagarjuna so perplexes many who come to his texts is his seeming willingness to embrace contradictions, on the one hand, while making use of classic reductio arguments, implicating his endorsement of the law of non-contradiction, on the other. Another is his apparent willingness to saw off the limbs on which he sits. He asserts that there are two truths, and that they are one; that everything both exists and does not exist; that nothing is existent or non-existent; that he rejects all philosophical views including his own; that he asserts nothing. And he appears to mean every word of it. Making sense of all of this is sometimes difficult. Some interpreters of Nagarjuna, indeed, succumb to the easy temptation to read him as a simple mystic or an irrationalist of some kind. But it is significant that none of the important commentarial traditions in Asia, however much they disagree in other respects, regard him in this light.[i] And indeed most recent scholarship is unanimous in this regard as well, again despite a wide range of divergence in interpretations in other respects. Nagarjuna is simply too committed to rigorous analytical argument to be dismissed as a mystic.
Jay L. Garfield and Graham Priest in Nagarjuna and the Limits of Thought
There's a fascinating discussion of this topic going on here.