Nāgārjuna (Devanagari:नागार्जुन, Telugu: నాగార్జున, Tibetan: ཀླུ་སྒྲུབ་ klu sgrub, Chinese: 龍樹, Sinhala නාගර්පුන) (ca. 150–250 CE) is widely considered the most important Buddhist philosopher after the historical Buddha. Along with his disciple Āryadeva, he is credited with founding the Madhyamaka school of Mahāyāna Buddhism. Nāgārjuna is also credited with developing the philosophy of the Prajñāpāramitā Sūtras and, in some sources, with having revealed these scriptures in the world, having recovered them from the nāgas (dragons). Furthermore, he is traditionally supposed to have written several treatises on rasayana alchemy as well as serving a term as the head of Nālandā University.