Epistemology is an important subject of study across several śāstras in the Indic knowledge tradition, in both Vedic and non-Vedic streams. Each of these knowledge systems systematically develops a science of knowledge i.e. examining what is knowable, through human cognition, what is inferable through methods of reasoning, but not perceivable, and what is unknowable within a system of thought. While theories of hermeneutics emerge most significantly from the tradition of Pūrva-mīmāṁsā, some important theories pertaining to epistemology are also notable in this system. In discussing what is knowable within a thought system, knowledge itself is often discussed and defined in various Hindu knowledge systems, with great precision.