The purpose of this thesis is to comparatively study Jaina Philosophy and Theravada Buddhist Philosophy. Jaina Philosophy and Theravada Buddhist Philosophy do not accept an authority of the Vedas and can be viewed both as atheistic Philosophies. They share a number of main opinions with each other. To study these philosophical systems through Western philosophical categaries-metaphysics, epistemology and ethics must be useful for understanding them widely and deeply. From the research it is found that Jaina Philosophy and Theravada Buddhist Philosophy have the similar concepts in three basic philosophical sides : a) metaphysically both systems accept the concept two ulimate realities-mind and matter, b) epistemologically they share a view the nature of knowledge is a release of mind from an ignorance and there are two levels of knowledge – worldly and transcendental, and c) ethically they have a same idea that to attain an ultimate goal of life is to get rid of defilements which is a cause of bondage. Though seemingly Jaina Philosophy and Theravada Buddhist Philosophy have a number of similar views, but after clear investigation it happens that there are two important differences in their views. These two are : a concept of mind and a concept of Karma. Jiva in Jaina Philosophy is substantial, eternal and unchanging. But mind or Citta in Theravada Buddhist Philosophy is non-substantial. It arises and decays momentarily. Karma according to Jaina Philosophy is material. It is an atom which forms when one acts and then is absorbed by Jiva. Karmic atoms absorbing Jiva will be in bondage until it can release itself from Karma. Karma in Theravada Buddhist Philosophy in a volitional action. Volition and some mental factors produce good and bad Karmas. Karma will be kept in subconsciousness (Bhavanga-citta) and by it mind will be in bondage till attains Nirvana. In Karma order, Jaina Philosophy takes a bodily action as a supreme one while Theravada Buddhist Philosophy gives a highest status to mental action. Because of this difference, these two philosophical systems differ in emphasizing the different views on actions. According to Jaina Philosophy, a bodily austerity is a necessary cause of Karma cessation, but in Theravada Buddhist Philosophy it is a mental austerity. Finally it is remarkable that the most important teaching of these two philosophical systems is an ethical. According to Jaina Philosophy and Theravada Buddhist Philosophy, philosophical ideas should bring happiness in actual life to man. Happiness can be attained by non-violence and mental development. Jaina Philosophy and Theravada Buddhist Philosophy are both a philosophy of life, not mere a dream philosophy.
