Buddhist thought rejects ideas of substance or substances as entities that endure through time and change. Speculation about the eternity of the world, its infinity, or the connections between the soul or mind and the body are not considered worthwhile. In the Theravada schools of thought, perceptual experience is believed to justify mind-independent entities, but we do not experience them directly. Some commentators hold that there are independent entities, otherwise our inference from experience that they exist could not be justified. Furthermore, we do not control what we perceive, which suggests that things exist outside of our perception. Others distinguish between reliable and unreliable sensory experience. Some Buddhists believe that both minds and bodies are collections of transitory perceptions.

According to the Madyhamika School, there can’t be individual objects because everything is dependent on everything else. However, enlightenment can result in an awareness of an underlying reality behind or beyond this flux. The Yog?car? branch of this school holds that because there are no minds, there is no one to see the truth and no way to discover it. Given the lack of substances (which would include minds), all that exist are mental states. Our lack of control over perception or the apparent objectivity of things is merely the effect of our own memories.

It should be evident at this point that Buddhism has grappled with the same kinds of questions about what really exists as those that have held the attention of Western philosophers throughout history. One difference is that, with the exception of ancient stoicism and epicurianism, and perhaps contemporary Buddhism, Western philosophers do not have life practices directly linked to their intellectual beliefs. Useful sources for philosophical comparison include Masao Abe and Steven Hein, Zen and Comparative Studies (1997); Dan Lusthaus, Buddhist Phenomenology: A Philosophical Investigation of Yogacara Buddhism (1997); and Anil Kumar Sarkar, Buddhism and Whitehead’s Process Philosophy (1991).