"There are nine classes of substances (dravya), some of which are non-atomic, some atomic, and others all-pervasive. The non-atomic ground is provided by the three substances of ether (ākāśa), space (dik), and time (kāla), which are unitary and indestructible; earth (pṛthvī), water (āpas), fire (tejas), and air (vāyu) are atomic composed of indivisible, and indestructible atoms (aṇu); self (ātman), which is the eighth, is omnipresent and eternal; and, lastly, the ninth, is the mind (manas), which is also eternal but of atomic dimensions, that is, infinitely small."