Indian 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. 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. 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 are also the Indian vāda (debate) literature and Tibetan bsdus grwa (collected topics) that 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 (6th– 7th 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. (shrink)

Mīmāṁsā, an Indian hermeneutics provides an exhaustive methodology to interpret Vedic statements. A formalism namely, Mīmāṁsā Inspired Representation of Actions has already been proposed in a preliminary manner. This paper expands the formalism logically and includes Syntax and Semantics covering Soundness and Completeness. Here, several interpretation techniques from Mīmāṁsā have been considered for formalising the statements. Based on these, instructions that denote actions are categorized into positive and prohibitive unconditional imperatives and conditional imperatives that enjoin reason, temporal action and goal. (...) These instructions are evaluated to three values S, V and N. If the instruction is executed with the intention of goal, then it acquires the value of S; if the intention of goal is present and the instruction is not executed, then it assumes the value of V; and if there is no intention of goal, then the instruction is evaluated to N. This formalism has also been applied in different computational settings such as AI planning, Robotics, task analysis and classification of natural language instructions. An outline of these applications and the comparison of this formalism with other relevant theories are also presented in this paper. (shrink)

This article is first in a series dedicated to issues in the intellectual history of Mīmāṃsā in early modern India and part of a larger effort to broaden the basis for understanding the new formulations of central topics of the Mīmāṃsā textual-ritual complex in this period. It examines how the Varanasi scholar Khaṇḍadevamiśra makes use of Navyanyāya tools of analysis by putting under the microscope the example of his investigation and new formulation of the signification of agent and agency by (...) the verbal affix in his ample analysis of the cognition of the meaning elements of a sentence. Authors of Mīmāṃsā works in the sixteenth and seventeenth centuries gradually and selectively adopt the tools and techniques of cognitive analysis and the characteristic new idiom elaborated by Navyanaiyāyikas a few centuries earlier. This process of adoption arises on the sidelines of the Advaita–Dvaita Vedānta controversy in South India, then subsequently flourishes in Varanasi, as I have followed elsewhere. In his analysis of the topic studied here, Khaṇḍadeva uses the new tools to revisit the Mīmāṃsā tradition in order to advance his new formulation while refuting certain Navyanyāya rival positions. (shrink)

As a Festschrift, this book celebrates and honours the scholarly achievements of Professor Jaysankar Lal Shaw, one of the most eminent and internationally acclaimed comparative philosophers of our times. Original works by leading international philosophers and logicians are presented here, exploring themes such as: meaning, negation, perception and Indian and Buddhist systems of philosophy, especially Nyaya perspectives. -/- Professor Shaw’s untiring effort to solve some of the problems of contemporary philosophy of language, logic, epistemology, metaphysics and morals from the perspectives (...) of classical Indian philosophers or systems of philosophy is deserving of a tribute. Chapters in this volume reflect the diverse aspects of Shaw’s contribution to comparative philosophy and are organised into four sections: Language, Epistemology, Mathematics and Logic, Ethics and Politics. -/- These chapters would appeal to anyone interested in philosophy or East-West thinking, including students and professionals. Graduates and researchers with interests in epistemology, metaphysics, political philosophy, logic and non-western philosophy will find this work highly relevant. (shrink)

Arthâpatti is a pervasive form of reasoning investigated by Indian philosophers in order to think about unseen causes and interpret ordinary and religious language. Its nature is a point of controversy among Mimamsa, Nyaya, and Buddhist philosophers, yet, to date, it has received less attention than perception, inference, and testimony. This collection presents a one-of-a-kind reference resource for understanding this form of reasoning studied in Indian philosophy. Assembling translations of central primary texts together with newly-commissioned essays on research topics, it (...) features a significant introductory essay. Readable translations of Sanskrit works are accompanied by critical notes that introduce arthâpatti, offer historical context, and clarify the philosophical debates surrounding it. Showing how arthâpatti is used as a way to reason about the basic unseen causes driving language use, cause-and-effect relationships, as well as to interpret ambiguous or figurative texts, this book demonstrates the importance of this epistemic instrument in both contemporary Anglo-analytic and classical Indian epistemology, language, and logic. (shrink)

The Conciliatory Character of Jaina Logic. In the previous pages there has been given an indication of the services rendered by the Jainas and N° Brihrna^1 H,e the Buddhists in the formation of the Mediaeval School of Indian Logic. Since the  ...

We present the Jaina theory of sevenfold predication as a 7-valued logic, in which every logical value consists in a 3-tuple of opinions. A question-answer semantics is used in order to give an intuitive characterization of these logical values in terms of opinion polls. Two different interpretations are plausible for the latest sort of opinion, depending upon whether "non-assertability" refers to incompleteness or inconsistency. It is shown hat the incomplete version of JL_{G} is equivalent to Kleene's logic K3, whereas the (...) inconsistent version of JL_{M} is equivalent to Priest's Logic of Paradox LP. Finally, it is argued that the Indian logics depart from Western logics by conflating truth and justified belief: the different preconditions for belief ascription accounts for the difference between pluralist and skeptic logics. (shrink)

The Fang Bian Xin Lun is a text on Buddhist logic which is thought to be the earliest one still to be extant. It appears in Chinese only (T1632). The great Italian indologist Giuseppe Tucci, believing that the text was originally a Sanskrit text, translated it into Sanskrit and gave it the title Upāyahṛdaya. The paper provides the historical background of the development of logic in Classical India up to the time of this text, summarizes its content and translates its (...) first section. (shrink)

This article aims to follow the process of adoption of Navya-Nyāya techniques of cognitive analysis in the school of Vedic hermeneutics, Mīmāṃsā, in the sixteenth and the seventeenth centuries, in the larger context of the spread of these techniques in India. I shall argue that this process arises in Mīmāṃsā on the sidelines of the Advaita-Dvaita Vedānta controversy in South India, then subsequently flourishes in Varanasi. These techniques are adopted gradually and selectively, for not all the Mīmāṃsā thinkers choose to (...) use them. (shrink)