釋氏稽古略 2.42

2.42

醫術　沙門于法開。是年入寂。開蘭公弟子也。善放光般若經。尤精醫法。穆帝甞召之。視脈知其不起乃不醫。或問曰。師高明剛簡。何以醫術經懷。開曰。明六度以除四魔之病。調九候以療風寒之疾。自利利人不亦可乎（本傳）。

Medical Arts: The śramaṇa Yu Fakai entered quiescence in this year. Kai was a disciple of Master Lan. He was skilled in the Pañcaviṃśatisāhasrikā-prajñāpāramitā Sūtra and was particularly proficient in the art of medicine. Emperor Mu once summoned him; examining his pulse, Kai knew he would not recover, and so did not treat him. Someone asked him, 'Master, you are elevated and discerning, firm and simple; why do you keep the art of medicine in mind?' Kai said, 'Clarifying the six perfections eliminates the illnesses of the four māras; regulating the nine pulse-states treats diseases of wind and cold. Benefiting oneself and benefiting others—is this not also fitting?' (His Biography).