"As these dosas, and especially the association between the gall and the fire, are already known in the Vedic literature, the tridosa theory cannot have been borrowed in India from Plato. On the contrary, as during the Persian domination of Greek Asian countries and a part of India, scientific intercourse has been easy, an influence of the Ayurvedic theories on those described by Plato is quite probable. In any way, we have several direct references in the Hippocratic Collection to the borrowing of some Indian drugs and Indian medicinal formulas in Greece. In the period of the expansion of Indian culture toward Central Asia and China, and toward Indo-China and Indonesia beyond the seas, Indian Ayurvedic medicine has been one of the main matters of export, along with astronomy, religions, and arts."