  The Nyāya-Vaiśeṣikas traditionally held that, within the total collection (sāmagrī) of causal factors leading to an event, there are three distinguishable types of cause, namely ‘substrate’ or ‘inherence’ causes (samavayi-kāraṇa), ‘non-substrate’ or ‘non-inherence’ causes (a-samavayi-kāraṇa), and ‘instrumental’ causes (nimitta-kāraṇa). This classification is repeated by The Manual of Reason (TS 43). A substrate cause is a substance in which the effect inheres. The substrate cause of a pot would be the pot-halves; of a cloth, the threads. This is because the Nyāya say that a whole inheres in its parts, and, so, if the effect (e.g. the pot) is a whole, its substrate causes are the parts in which it inheres. If the effect is an object’s coming to have a new property (e.g. the tree’s being felled), the substrate cause is the object (the tree). Note that, in spite of a certain similarity, the notion of a substrate cause is not the same as Aristotle’s “material” cause, for (i) the parts of an object are not necessarily identical with the material from which it is composed, and (ii) even an immaterial substance can be a substrate cause, for example the soul, which is the substrate cause of epistemic events.