Prabhakara; He defines valid knowledge as apprehension (anubhuti). All apprehension is direct and immediate and valid per se. ‘all cognitions as cognitions are valid; their invalidity is due to their disagreement with the real nature of their objects.’

Prabhakar’s theory of knowledge: triputipratayaksavada. He regards knowledge as self luminious (svaprakasha). It manifests itself and needs nothing for its manifestation. It is not eternal. Every knowledge according to him has triple manifestation− the cognition of the self as the knower (ahamvitti), the cognition of the object as the known (visayavitti), and the self-conscious cognition (svasamvitti).