Chi-tsang (549-623). The greatest systematizer of the San-lun school in China, and ironically, its last great master. The son of a Parthian father (who joined the Buddhist order not long after his birth) and a Chinese mother, he became a monk sometime between the ages of 7 and 13, and began the study of San-lun (or Madhyamaka) doctrine immediately under Fa-lang (507-81). Living through the turbulent period when China was reunited under the Sui dynasty, which then gave way to the T'ang dynasty, Chi-tsang worked to preserve the corpus of Buddhist literature against the depredations of the times. A prolific commentator and lecturer, he was invited to give talks at the court of the Sui emperor and honoured as a National Teacher. During his lifetime, Chih-i of the T'ien-t'ai school was gaining notice for his doctrinal elaborations that brought the Two Truths of San-lun, seen as separate from each other, into the greater synthetic vision of his Three Truths. Perhaps in response to this, Chi-tsang formulated a deeper articulation of the traditional Two Truths in such a way that they interacted through three levels of dialectical critique, and in the final analysis achieved a similar kind of synthesis. However, after Chi-tsang's death no further masters arose to keep the San-lun tradition alive, and its place at the forefront of Buddhist scholarship was taken by the T'ien-t'ai and Hua-yen schools.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)