Introduction Epistemology is considered as an essential part of philosophy. In the course of the development of the Indian systems, interest in epistemology gradually increased and it began to claim a large share in the philosophical discussions in almost every School of thought. The term 'epistemology' is derived from the Greek words 'Episteme' (knowledge or science) and 'Logos' (knowledge or information). William L. Rease defined Epistemology as the study of the theory of knowledge. Various philosophers have tried to define the term in their own way. Robert Audi called it as the study of (a) the defining features, (b) the substantive conditions, and (c) the limits of knowledge and justification. The study of the nature of knowledge is one of the core issues in epistemology. There is considerable agreement with regard to acceptability of knowledge as a value, but agreement about the nature of knowledge is not there. Philosophers disagree as to what the nature of knowledge is, and how it is acquired. All these issues belong to Epistemology such as what is knowledge, what is the origin of knowledge, what is the scope of knowledge, what are the various sources of knowledge and what is the validity of knowledge? J.F.Ferrier (Institute of Metaphysics, 1854) divided philosophy into ontology and epistemology. The word 'Epistemology' denotes the theory of valid knowledge, an important province of philosophical theory, and the doctrine on man's ability to cognize reality, on the sources, forms and methods of cognition, the truth and the ways of attaining it. The English word 'knowledge' translates the Sanskrit word jnana. The concept of knowledge has been source of attraction for thinkers all over the world since long. Some thinkers hold knowledge to be an act, some others regard it as a relation, and according to some it is self subsistent and for some others it is a quality1 . In Indian epistemology, two words are used to mean knowledge. They are jnana and prama. Jnana means all kinds of knowledge, true or false. When reality reveals true knowledge it is called prama or valid knowledge,