楞伽阿跋多羅寶經註解 1.141

1.141

問五明法及伎術。五明者，一曰內論，謂一切佛法；二曰外論，有四種，曰因、曰聲、曰醫方、曰工巧。此五各能生智，故云明處。

This asks about the teachings of the five fields of knowledge (vidyāsthānas) and technical arts. As for the five fields of knowledge: the first is internal treatises, meaning all Buddhist teachings; the second is external treatises, of which there are four kinds: logic, linguistic science, medicine, and arts and crafts. Because each of these five can generate wisdom, they are called fields of knowledge.