Buddhist logic

Buddhist philosophers have investigated the techniques and methodologies of debate and argumentation which are important aspects of Buddhist intellectual life. This was particularly the case in India, where Buddhism and Buddhist philosophy originated (see Buddhist philosophy, Indian §4; Epistemology, Indian schools of §1; Knowledge, Indian views of; and Inference, Indian theories of). But these investigations have also engaged philosophers in China, Japan, Korea, and Tibet, and many other parts of the world that have been influenced by Buddhism and Buddhist philosophy (see Buddhist philosophy, Chinese; Buddhist philosophy, Japanese; Buddhist philosophy, Korean; and Tibetan philosophy).

Several elements of the Buddhist tradition of philosophy are thought to be part of this investigation. There are interesting reasoning patterns discernible in the writings of Buddhist philosophers. For instance, the Mādhyamika philosopher Nāgārjuna presents arguments for the emptiness of all things in terms of catuṣkoṭi (four ‘corners’: roughly speaking, truth, false, both, neither). There is also the Indian vāda (debate) literature and the Tibetan bsdus grwa (collected topics), both of which list techniques of debates.

The main interest here is the tradition of Buddhist philosophy, sometimes referred to as Pramāṇavāda, whose central figures are Dignāga (approx. 480–540 CE) and Dharmakīrti (sixth–seventh| century CE) (see Dignāga and Dharmakīrti). This philosophy is understood to be the Buddhist school of logic-epistemology. ‘Pramāṇavāda’ is not a doxographical term traditionally used to refer to a recognised school of Buddhist philosophy. It is a conventional term that is sometimes used in modern literature. Nevertheless, in what follows, we think of it as a tradition within Buddhist philosophy, and ‘Buddhist logic’ refers to what is developed in this tradition.

Buddhist logicians have systematically analysed the kind of reasoning involved in acquiring knowledge. They hold that there are valid ways to reason that are productive of knowledge. In what follows, some of the main elements of their analyses will be described. Note, however, that, while exegetical studies of Buddhist texts are important, we must step back from them and consider what is involved in taking a Buddhist approach to logic in light of modern formal logic. This analysis will be done against the backdrop of the contemporary literature on logic and related subjects in contemporary philosophy to make sense of the logical studies by Buddhist logicians.