Dignāga (c. 480–540) and Dharmakīrti (c. 6-7th century) were Buddhist philosophers who developed a system of epistemology (pramana) and logic in their debates with the Brahminical philosophers in order to defend Buddhist doctrine. This tradition is called "those who follow reasoning" (Tibetan: "rigs pa rjes su 'brang ba"); in modern literature it is sometimes known by the Sanskrit ""pramāṇavāda"", or "the Epistemological School." They were associated with the Yogacara and Sautrantika schools, and defended theories held by both of these schools. Dignaga's influence was profound and led to an "epistemological turn" among all Buddhist and also all Sanskrit language philosophers in India after his death. In the centuries following Dignaga's work, Sanskrit philosophers became much more focused on defending all of their propositions with fully developed theories of knowledge.