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NYĀYA AND JAINA EPISTEMOLOGY
rival systems are criticized by Nyāya philosophers. According to Nyāya, knowledge is to be regarded as an effect and like any other effect, it origins in joint collocation of causes. There is no transcendental element involved in the production of knowledge. Therefore, Sānkhya view is rejected by Nyāya. Similarly Buddhist view that knowledge shows itself as both knowledge and its object is also considered as irrational and, therefore, untenable by Nyāya philosophers.
Valid knowledge is defined as definite knowledge of an object which is true and presentational in character. "Gangesa maintains that pramā is that which informs us of the existence of something in a place where it really exists?.” It is clear that Nyāya view of valid knowledge resembles correspondence theory of western realists.
The nature of the knowledge as valid or invalid depends upon the four means of valid knowledge. The means of knowledge are the operative causes, the determining conditions of origin of valid knowledge. Nyāya logic is both formal and material. It is interested in consistency as well as in truth. This helps us to have a right apprehension of an object as well as to test the validity of knowledge.
It discusses the different ways in which knowledge is acquired. These are the sources of valid knowledge which are :i. Perception
ii. Inference iii. Comparison iv. Testimony
These are not merely ways and means by which human mind acquires knowledge that is psychological processes by which knowledge as mental content is gained,
