Indian logic can be traced back to some centuries B.C. It seems to have developed independently from Greek logic, even if there are similarities and parallels. Ancient Indian logic was born in the context of debate on religious and philosophical matters. In the mediaeval period from about the 4th century on, logic evolved in dealing with problems of valid knowledge, i.e. perception and inference

• Problems of transcribing avinaabhaava into predicate logic[PDF], 91 k Opens new window Translating ancient logical texts into modern symbolic logic can be a valuable method of getting access to an otherwise incomprehensible train of thought. Representing a definition or an argument in symbolic form, carries the risk of severely twisting the underlying ideas. Thus the use of modern symbolic logic is often of doubtful value for interpretational purposes.


• Stanislaw Schayer's Research on Nyaaya. Journal of Indian Philosophy 32: 295-319,2004[PDF]
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  Nyaaya denotes the oldest Indian logic. One main topic of Nyaaya is the five-membered scheme which, since its discovery in the West, has often been compared to Aristotelian syllogistic. St. Schayer was the first Western Indologist who used modern Predicate Logic for formulating the "Indian syllogism" in symbolic outfit. In this paper we discuss in detail the problematic parts of such a formalization of an ancient logic.


• Using Formulas for the Interpretationof Ancient Indian Logic [PDF], 91 k Opens new window
Utilising western logical concepts and formalisms in a naive manner for the research on ancient Indian logic is not without risks. There are some in-built limitations of modern formal logic which prevent it from being the "natural universal instrument" for the understanding of each and every logical system.


• Das Rad der Gründe [PDF]
  612 k (German language) Opens new window Dignaga's hetucakra (The wheel of reason) was his first work on formal logic. It may be regarded as a bridge between the older doctrine of trairuupia and Dignaga's own later theory of vyaapti which is a concept related to the Western notion of implication.