In this book, Harirama Tarkavagisa critically assesses the Mīmāṃśa theory of self-luminosity of knowledge. According to Prabhākara, the knower, the object of knowledge and the knowledge itself are apprehended in one go. The Bhaṭṭa Mīmāṃsakas hold that knowledge is inferred through a property called knownness. Murāri Miśra, another Mīmāṃsaka philosopher, holds that knowledge is known in a subsequent knowledge called introspection. Harirāma, following the footsteps of Gaṅgeśa, argues that since sometimes doubt regarding the validity of knowledge arises in the third moment after the origin of knowledge, the validity of the knowledge is apprehended by something other than the totality of the causal conditions of that knowledge. Harirama further argues that there is something wrong with the thesis that knowledge is self-luminious.