In the scriptures considered sacred by Hindus, members of Hindu society are divided into four castes, namely Brāhmaṇa, Kṣatriya, Vaiśya and Śūdra. They are supposed to be based on birth and specific professions are assigned to them. According to orthodox schools of Indian philosophy, like Nyāya, Vaiśeṣika and Bhāṭṭa Mīmāṃsā, this four-fold division of castes is based on a natural classification determined by the presence of four incompatible universals, namely brāhmaṇatva, kṣatriyatva, vaiśyatva, and śūdratva. These universals—like “cow-ness” (gotva), “horse-ness” (aśvatva), etc.—are eternal properties, each of them being one, and present in many individuals that exemplify it. According to Buddhists, all things are impermanent and unique; and hence, there are no common as well as eternal universals. Prābhākara Mīmāṃsakas and Jainas admit the existence of universals, as well as of common properties that cannot be treated as universals, but are known as upādhi (“imposed properties”). According to both these schools, brāhmaṇatva, etc. are instances of upādhi. It may be noted here that while Prābhākara Mīmāṃsakas admit the authority of the Vedas and the tenability of the caste system, neither of the two is admitted by the Jainas.