 A rejection of the supernatural is the point of minimal agreement amongst naturalists of all types, but there is no consensus regarding the boundary between natural and supernatural. Most schools of Indian philosophy identify nature with the empirical world or the world of experience. Two extreme views about the empirical world are available to Indian theory. The Advaita Vedāntins declare the world of experience unreal, an apparent transformation of the eternal and unchanging ultimate conscious principle. To the materialist Cārvākas, on the other hand, this world is real and it is composed of physical matter, consciousness is an emergent property of matter and self is nothing but conscious material body. They were also known as svabhāvavādins (a term translatable as “naturalists”) because to discard everything supernatural from their world-view they subscribe to a doctrine which holds that the occurrence of an effect is not determined by its cause but by its essential nature, thus making causation entirely redundant. This is indeed a unique move in the history of naturalism, for all types of naturalism in the West are intimately connected with the provision of a causal account of the world or of nature. In terms of our earlier taxonomy, the Advaita Vedāntins might be branded as non-naturalist and the Cārvākas as hard naturalist. In between these two lie the Buddhists, the Jainas, the Nyāya-Vaiśeṣikas and the Sāṃkhya-Yoga philosophers, whose accounts of the empirical world need to be analysed carefully if we are accurately to place them. Two questions, the answers to which will help to discern naturalist traits in these systems, are: what are the ultimate constituents of the empirical world, and what is the accepted model of causation for a particular school? For the bounds of nature are to be determined by the nature of real entities as admitted in a system and the nature of causal connection amongst these entities. If only physical things governed by the rules of mechanical causation are taken to be natural, then attempts would be made either to reduce psychological, biological, social, moral and mathematical entities to the physical or to establish somehow their causal relevance to the physical world.