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Padārtha is a Sanskrit word that refers to "categories" in Vaisheshika and Nyaya schools of Hindu philosophy. The term is a composite of pada (word, phrase) and artha (meaning), connoting in philosophical terms "a metaphysical correlate", or in other word categories that are different, distinct types of existent.
The concept was introduced by Kanada, the founder of Vaisheshika school. He suggested six padarthas in Vaisheshika Sutra. Later scholars, particularly of the Navya Nyaya school, added abhava, bringing the list to seven, states Ganeri: substance (dravya), quality (guṇa), motion or action (karma), universal (sāmānya), particularity or differentiator (viśeṣa), inherence (samavāya), and absence (abhāva). Each of the seven categories were further sub-divided in an attempt to explain the nature of universe, repetitive phenomenon and existence of living beings. For example, these schools proposed nine types of substance, twenty four types of quality, and so on.