Nyāya Sūtras
The Nyāya Sūtras is an ancient Indian Sanskrit text composed by , and the foundational text of the Nyaya school of Hindu philosophy. The date when the text was composed, and the biography of its author is unknown, but variously estimated between 6th-century BCE and 2nd-century CE. The text may have been composed by more than one author, over a period of time. The text consists of five books, with two chapters in each book, with a cumulative total of 528 aphoristic sutras, about rules of reason, logic, epistemology and metaphysics.
The Nyāya Sūtras is a Hindu text, notable for focusing on knowledge and logic, and making no mention of Vedic rituals. The first book is structured as a general introduction and table of contents of sixteen categories of knowledge. Book two is about pramana, book three is about prameya or the objects of knowledge, and the text discusses the nature of knowledge in remaining books. It set the foundation for Nyaya tradition of the empirical theory of validity and truth, opposing uncritical appeals to intuition or scriptural authority.
The Nyaya sutras cover a wide range of topics, including Tarka-Vidyā, the science of debate or Vāda-Vidyā, the science of discussion. The Nyāya Sutras are related to but extend the Vaisheshika| epistemological and metaphysical system. Later commentaries expanded, expounded and discussed Nyaya sutras, the earlier surviving commentaries being by Pakṣilasvāmin Vātsyāyana, followed by the Nyāyavārttika of Uddyotakāra, Vācaspati Miśra's Tātparyatīkā, Udayana's Tātparyapariśuddhi, and Jayanta's Nyāyamañjarī.
Author and chronology
The Nyaya-sutras is attributed to Gautama, who was at least the principal author. According to Karl Potter, this name has been a very common Indian name, and the author is also reverentially referred to as Gotama, Dirghatapas and Aksapada Gautama. Little is known about Gautama, or which century he lived in. Scholarly estimates, based on textual analysis, vary from the 6th century BCE, making him a contemporary of Gautama Buddha and Mahavira, to as late as the 2nd century CE. Some scholars favor the theory that the cryptic text Nyaya-sutras was expanded over time by multiple authors, with the earliest layer from about mid-first millennium BCE that was composed by Gautama. The earliest layer is likely to be Book 1 and 5 of the text, while Book 3 and 4 may have been added last, but this is not certain.It is likely, states Jeaneane Fowler, that Nyaya and the science of reason stretch back into the Vedic era; it developed in the ancient Indian tradition that involved "dialectical tournaments, in the halls of kings and schools of Vedic philosophers", and Gautama was the one who distilled and systematized this pre-existing knowledge into sutras, or aphoristic compilations called nyayasutras.
The Nyaya school of Hinduism influenced all other schools of Hindu philosophy, as well as Buddhism. Despite their differences, these scholars studied with each other and debated ideas, with Tibetan records suggesting that Buddhist scholars spent years residing with Hindu Nyaya scholars to master the art of reasoning and logic. This cooperation has enabled scholars to place the currently surviving version of the Nyayasutras, to a terminus ante quem date of about the 2nd century CE, because one of the most famous and established Buddhist scholars of that era, Nagarjuna, explicitly states, "sutra 4.2.25 is addressed against the Madhyamika system" of Buddhism. Other ancient Buddhist texts confirm that Nyayasutras existed before them, and the text is considered the primary text of old Nyaya school of Hinduism.
Structure
The text is written in sutra genre. A sutra is a Sanskrit word that means "string, thread", and represents a condensed manual of knowledge of a specific field or school. Each sutra is any short rule, like a theorem distilled into few words or syllables, around which "teachings of ritual, philosophy, grammar or any field of knowledge" can be woven. Sutras were compiled to be remembered, used as reference and to help teach and transmit ideas from one generation to the next.The Nyayasutra is divided into five books, each book subdivided into two chapters each. The structure of the text is, states Potter, a layout of ahnikas or lessons served into daily portions, each portion consisting of a number of sutras or aphorisms. The architecture of the text is also split and collated into prakaranas or topics, which later commentators such as Vatsyayana and Vacaspati Misra used to compose their bhasya, ancient texts that have survived into the modern era. There are several surviving manuscripts of the Nyayasutras, with a slight difference in number of sutras, of which the Chowkhamba edition is often studied.
| Book | Chapter | Number of sutras | Topics |
| 1 | 1 | 41 | Subject matter and statement of purpose of the text. Four reliable instruments of correct knowledge. Definitions. Nature of argument and nature of the process of valid proof. |
| 1 | 2 | 20 | How to analyze opposing views, presents its theory of five-membered arguments, correct conclusions are those where contradictions do not exist, theory of reasoning methods that are flawed, what is a quibble and how to avoid it. |
| 2 | 1 | 69 | Presents its theory of Doubt. Discusses epistemology, when perception, inference and comparison is unreliable and reliable. Theory that the reliability of testimony depends on the reliability of the source. Theory that the testimony in the Vedas are a source of knowledge and inconsistencies are either defects or choices in the text, the best way to understand the Vedas is to divide it into three: injunction, descriptions and reinculcations. |
| 2 | 2 | 71 | Instruments of knowledge are fourfold, Confusion caused by presumption and prejudice, Sound is noneternal theory, Theory of three meaning of words |
| 3 | 1 | 73 | presents its theory of body, followed by theory of sensory organs and their role in correct and incorrect knowledge, states that the soul is not a sense organ nor an internal organ. |
| 3 | 2 | 72 | presents its theory of soul, that the essence of a person and source of judgments is the soul, states its "judgment is non-eternal" theory, presents theory of Karma |
| 4 | 1 | 68 | Presents its theory of defects, then its theory that "everything has cause, and consequences", and its "some things are eternal, some non-eternal" theory. Defines and describes Fruits, Pain, Release. |
| 4 | 2 | 50 | Presents correct knowledge is necessary and sufficient to destroy defects. Both whole and part must be known. Establishes external world exists, and phenomenon are as real as objects. Refutes the "everything is false" theory. Presents ways to produce and maintain correct knowledge, Need to seek and converse with those with knowledge. |
| 5 | 1 | 43 | 24 futile rejoinders, how to avoid errors and present relevant rejoinders |
| 5 | 2 | 24 | 22 ways of losing an argument |
Content
The first sutra 1.1.1 of the text asserts its scope and the following sixteen categories of knowledge as a means to gain competence in any field of interest:These sixteen categories cover many sections of the text. The verse 1.1.2 of the Nyāya Sūtra declares the text's goal is to study and describe the attainment of liberation of soul from wrong knowledge, faults and sorrow, through the application of above sixteen categories of perfecting knowledge.
Means of attaining valid knowledge
The Nyaya-sutras assert the premise that "all knowledge is not intrinsically valid", that "most knowledge is not valid unless proven" and "truth exists whether we human beings know it or not". However, states Fowler, the text accepts the foundation that "some knowledge is self evident" and axiomatic in every field of knowledge, which can neither be proven nor needs proof, such as "I am conscious", "I think" and "soul exists". Furthermore, the text presents its thesis that knowledge is not self-revealing, one must make effort to gain knowledge and this is a systematic process that empowers one to learn correct knowledge, and abandon incorrect knowledge.The Nyāya sutras asserts and then discusses four reliable means of obtaining knowledge, viz., Perception, Inference, Comparison and Reliable Testimony.
Pratyaksha: Perception
The Nyayasutras assert that perception is the primary proper means of gaining true knowledge. All other epistemic methods are directly or indirectly based on perception, according to the text, and anything that is claimed to be "true knowledge" must be confirmed or confirmable by perception. This it terms as the doctrine of convergence, and this doctrine includes direct or implied perception. Gautama defines perception as the knowledge that arises by the contact of one or more senses with an object or phenomenon. Gautama dedicates many sutras to discuss both the object and subject in the process of perception, and when senses may be unreliable. Erratic eyesight or other senses can be a source of doubt or false knowledge, as can prejudgmental or prejudicial state of mind, states the Nyayasutras.The text asserts Pratyaksa leads to Laukika or ordinary knowledge, where the five senses directly and clearly apprehend a reality, and this is true definite knowledge according to the text. It defines indefinite knowledge as one where there is doubt, and the text gives an example of seeing a distant stationary object in the evening and wondering whether it is a post or a man standing in the distance. In some of these cases, states Nyayasutras, correct knowledge is formulated by the principle of cumulative evidence. Manas is considered an internal sense, in the text, and it can either lead to correct or incorrect knowledge depending on how it includes, excludes or integrates information. These ideas are compiled, in later chapters of the text, into its treatise on Aprama.