The categories in VaiŚeṣ ika:

The chapter enumerates the ontological categories of the Vaiśeṣika school, perhaps one of the earliest of the systemized darśana-s in the Indic tradition. The categories numbering six (and later seven) form the core of the metaphysics or one might even call natural philosophy, which had influence on other systems, particularly the Nyāya. The belief among the Vāiśeṣikas is that anything which exists and can be given a name and thus belongs to the class or subclass of ‘padārtha’, In other words, designation depends on knowability; therefore that which has the capacity to be the object of knowledge is padārtha.