Abstract: Knowledge is divided in two kinds – valid knowledge (yathārtha jňāna and ayarthārtha jňāna) and invalid knowledge in Indian philosophy. Valid knowledge is called pramā. Pramāṇa is the means or instrumental cause of valid knowledge or pramā. There are several kinds of pramāṇa in Indian philosophy. Upamāna pramāṇa is another kind of pramāṇas in Indian philosophy. According to the nyāya philosophy upamāna is an independent source of knowledge and we get upamiti pramā from upamāna pramāṇa. Upamāna pramāṇa is the instrumental cause or karaṇa of upamiti and upamiti is the resultant knowledge of upamāna pramāṇa. Upamiti is the knowledge of śakti or relation of words to their meaning.Upamāna plays a great role in the knowledge theory and practical life. Here I have tried to explained how did use the upamāna pramāṇa in the Sanskrit and Bengali literature.
Ranjit Shaw (Mon,) studied this question.