一個對二元交互論身心如何可能互動問題的佛學解答

內容摘要：本文的主旨是嚐試從佛學中的「人是五蘊因眾緣和合而成」、「身心不二」（non-duality）及《般若波羅密多心經〉中所闡述「五蘊皆空」等教義，而針對笛卡兒的二元交互論（dualistic interactionism）中一個重要問題「如身體（物質）與心靈（非物質）各為獨立存在的實體，則物質與非物質兩者之主動如何可能？提出一個答案。另外，本文亦會觸及佛學本身兩個相關問題：東西方佛教學者在探討身心（或色名）問題時大都倒重在闡述身心兩者之間的關聯性（relation），而不是更根本且密切相關的兩個問題：「身心不二的本質為何？」及「身心兩者間的關聯性何以可能？」。前者的答案為後者的基礎，而後者則亦是具有笛卡兒二元交互論問題的一種較弱特徵或意涵。因身心如無某些共同的本質或本性，則論說兩者間有關聯性雖是可以，但其似乎不夠完備而會令人產生疑慮的。因此，本文希望藉由《般若波羅密多心經》中「五蘊皆空」之佛理，而來解開笛卡兒二元交互論中身心如何可能互動的問題，以及釐清佛教本身兩個相關的問題。

關鍵字

二元交互論；「身心不二」；「五蘊皆空」

並列摘要

This essay tries to resolve an important problem of Cartesian dualistic interactionism, which is that if mind and body are two distinct and independent substances in their nature, how the interaction between them is possible, with Buddhist three teachings : ＂person is made up of five aggregates (pañca-skandha) given patītyasamutpāda,＂＂the mind-body is non-duality,＂ and most importantly ＂the five aggregates are emptiness (śūnyatā) based on the Prañjā Pāramitā Heart Sutra.＂ Besides, we will also touch two relevant issues of Buddhism. When most of the Buddhist scholars discuss the mind-body problem, they tend to focus on the relation between mind and body rather than two fundamental questions: ＂What is the nature of non-duality of mind and body?＂and ＂How is it possible for mind and body to have a relation?＂ The answer for the former is the basis for the latter, and the latter bears a weak sign (or meaning) of the problem of Cartesian dualistic interactionism. For if there is not a common nature (or ground) of mind and body, it is problematic to state that there is a relation between them. Therefore, we employ the teaching that the five aggregates are emptiness in Prañjā Pāramitā Heart Sutra to resolve the problem of Cartesian dualistic interactionism and to clarify the Buddhist two fundamental questions.