All objects of experience can be classified into six categories, dravya (substance), guṇa (quality), karma (activity), sāmānya (generality), viśeṣa (particularity) and samavāya (inherence). Later Vaiśeṣika s (Śrīdhara and Udayana and Śivāditya) added one more category abhava (non-existence).he earliest systematic exposition of the Vaisheshika is found in the Vaiśeṣika Sūtra of Kaṇāda (or Kaṇabhaksha). This treatise is divided into ten books. The two commentaries on the Vaiśeṣika Sūtra, Rāvaṇabhāṣya and Bhāradvājavṛtti are no more extant.