The Vaiśeṣika world-view propounds that the four substances enumerated in its list, namely earth (pŗthvī), water (jala), fire (tejas) and air (vāyu), are of two types – eternal and non-eternal. The former kind of these four substances is held to be atomic; atoms (paramāṇus) are held to be the ultimate, eternal parts of these four substances and are of four types – earthly, watery, fiery and airy. They are eternal, since they are not produced by any cause and are ever-existent. 1 All the multifarious objects of the gross, visible world are held to be the products of these four types of atoms only.