Tsong-kha-pa bLo bzang grags-pa was one of the most profoundly influential minds in Tibetan history. His understanding of numerous aspects of Buddhist doctrine became paradigmatic and the basis for further commentary and dispute on most of the subsequent developments in Tibetan Buddhist thought.
Perhaps most philosophically significant is Tsong-kha-pa's interpretation of the Madhyamaka philosophy of Nagarjuna. This work is a translation and study of the first chapter of Tsong-kha-pa's previously untranslated commentary on Nagarjuna's Mulamadhyamakakarika, the Rigs pa'i rgya mtsho or "Ocean of Reasoning". This commentary follows the interpretative system of the Indian Madhyamaka author Candrakirti as described in his Prasannapada and Madhyamakavatara. This system, called the Prasangika, distinguishes itself from other interpretive approaches in its reliance on reductio ad absurdum arguments and its rejection of systematic epistemology.
Tsong-kha-pa claims to follow Candrakirti's Prasangika approach yet also maintains that phenomena are epistemologically grounded and valid, accepting the epistemological systems of Buddhist philosophers Dharmakirti and Dignaga. These two trends of Buddhist thought are skillfully interwoven in Tsong-kha-pa's presentation of Nagarjuna's text. The author discusses some of the non-Madhyamaka influences found in Tsong-kha-pa's Madhyamaka as well as examining how and in what ways this differs from the thought of Candrakirti.
