A pramana is a criterion for valid argument in Indian philosophy. From its earliest days Indian philosophy sought to delimit the grounds upon which valid argument could be made. Different philosophical schools varied widely as to which grounds they accepted, but they all had from one to six or more explicit pramanas.
Examples of pramanas are pratyaksha, or direct perception; ANUMANA, or inference; and SHRUTI, or scripture. The CHARVAKAS, the Indian materialists, believed that only direct perception or pratyaksha was valid and there is no point in trying to draw any conclusions by analogy or any other way. The MIMAMSA school, on the other hand, saw shruti or the Vedic scripture to be the most important pra-mana. NYAYA-VAISHESHIKA, the most philosophical school, strongly relied on inference, or anumana.
Further reading: S. N. Dasgupta, The History of Indian Philosophy (Delhi: Motilal Banarsidass, 1971–75); R. I. Inagalalli, Sabda Pramana, an Epistemological Analysis (Delhi: Sri Satguru, 1988).
Encyclopedia of Hinduism. A. Jones and James D. Ryan. 2007.