The chief causes of aggravation and calming of the doshas

The doshas are aggravated or calmed through external and internal causes, through the rising (udaya) or premature ripening (udīraṇā) of karma, and through the fourfold set of substance, place, time and state. An editorial note explains that every result needs an external and an internal cause: for the cure of disease the external causes are medicine, care and treatment and the internal cause is the rising of the karma that brings comfort (sātāvedanīya); it defines udaya and udīraṇā, and says that unfavourable substance, place, time and state aggravate the doshas while favourable ones calm them.