Concept of self or soul in the Carvaka pilosophy
The most important doctrine in the Carvaka system is that perception (pratyaksha) is the only means of valid knowledge. Since there is no entity called ‘soul’ as distinct from the body, as given in perception, there is no place for such an entity in this system.
According to Carvaka, when the four forms of matter, namely, earth, water, fire and air combine in a peculiar way, there results what we call a body. Life breath (prana) and consciousness are present only in such a body. This body is the soul and there is nothing permanent or eternal apart from the body. There is no life-breath or consciousness in the minute particles (kana) of matter, which are the basic constituents of matter, when they are in a disjoined state. At that time, they remain in a lifeless and Carvaka insentient state.
However, due to that very peculiar and mutual combination or mixture of these elements, there appears life-breath and consciousness. Thus what we call soul is nothing but the conscious body. In other words, consciousness or mind is an epi-phenomenon, a by-product of matter. Such a by-product is possible because qualities not possessed by the elements individually, maya rise in the aggregate constituted of them. For example, an intoxicating quality arises from the mingling of yeast and other ingredients, though this quality is not possessed by the ingredients when they exist by themselves.
To quote: “sarvasiddhantasarasamgraha.”
“That intelligence which is found to be embodied in modified forms of the non-intelligent elements is produced in the same way in which the red colour is produced from the combination of betel, areca-nut and lime”. Thought is a function of matter. Since consciousness is a property of the body, with the dissolusion of the body consciousness disappears and each of its constituent elements is mingled with its kind leaving behind only ashes and dust. Transmigration, retribution etc. are meaningless words.