Nāgārjuna is one of the earliest systematic philosophers classified as a Mahāyāna Buddhist, and he is generally regarded as the founder of the Mādhyamika lineage. This school, it was suggested above, tends to focus on emptiness and on negation, in the style of the Heart Sūtra. Other sūtras that are held in high regard by Mādhyamikas, and
considered to expound the highest teachings (as opposed to merely useful teachings employed as expedient means) include the Vimalakīrti Sūtra and the Mahāratnakūṭa.
Yet, it has been argued that Nāgārjuna‘s main work, the Mūlamadhyamakakārikā (MMK), is a commentary upon an older Pāli text, the Kaccāyanagotta Sutta (Kalupahana 1996, 5), which comprises a response to the question "To what extent is there right view?" The Buddha replies, in this sūtra, that there are two extreme positions to be avoided; these are, briefly, the belief in existence, and its contrary, the belief in nonexistence. The Enlightened One avoids making claims about either, and teaches via a
'Middle Way,‘ which is identified with pratītyasamutpāda, the doctrine of Dependent Co-origination (S ii 17; Thanissaro).