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Reasoning and Logic

Indian logic is considered as one of the three original traditions of logic, alongside the Greek and the Chinese logic. The Indian tradition continued to develop through early to modern times.
  • Medhatithi Gautama founded the anviksiki school of logic.
  • Paaini developed a form of logic for his formulation of Sanskrit grammar.
  • Logic is described by Chanakya in his Arthashastra.
  • Vaisheshika espouses a form of atomism and postulates that all objects in the physical universe are reducible to a finite number of atoms, which is proposed by Kanada.
  • Nagarjuna refined the Catuskoti tetralemma (four corner argument) form of logic.

The Nyaya ("recursion") school of philosophical speculation is based on texts known as the Nyaya Sutras, which were written by Gotama in around the 2nd century CE. According to the Nyaya school, there are exactly four sources of knowledge (pramanas): perception, inference, comparison and testimony. Knowledge obtained through each of these can, of course, still be either valid or invalid.

Jain logic developed and flourished from 6th century BCE to 17th century CE. According to Jains, the ultimate principle should always be logical and no principle can be devoid of logic or reason. These Jain philosophical concepts made most important contributions to the ancient Indian philosophy, especially in the areas of skepticism and relativity. Kundakunda (2nd century CE), exponent of Jain mysticism and Jain nayas dealing with the nature of the soul and its contamination by matter, author of Pañcastikayasara (Essence of the Five Existents), the Pravachanasara (Essence of the Scripture) and the Samayasara (Essence of the Doctrine). Umasvati or Umasvami (2nd century CE), author of first Jain work in Sanskrit, Tattvarthasūtra, expounding the Jain philosophy in a most systematized form acceptable to all sects of Jainism. Siddhasena Divakara (5th century CE), Jain logician and author of important works in Sanskrit and Prakrit, such as, Nyayavatara (on Logic) and Sanmatisūtra (dealing with the seven Jaina standpoints, knowledge and the objects of knowledge) Haribhadrasuri (8th century CE), a Jaina thinker, author and great proponent of anekantavada and classical yoga, as a soteriological system of meditation in Jaina context. His works include Ṣaḍdarśanasamuccaya and Yogabindu. Aacharya Hemacandra (1089–1172 CE) - a Jaina thinker, author, historian, grammarian and logician. His works include Yogaśastra and Trishashthi Shalaka Purusha charitra. Mahopadhya Yaśovijayaji (1624–88 CE) – Jain logician and considered as intellectual giant to contribute to Jaina philosophy. Acharya Mahapragya (1920–2010 CE);– Jain logician and considered as intellectual giant and encyclopedia to contribute to Jaina philosophy.

Buddhist logic (called Pramana) flourished from about 500 CE up to 1300 CE. The three main authors of Buddhist logic are Vasubandhu (400–800 CE), Dignaga (480–540 CE), and Dharmakīrti (600–660 CE).

The Navya-Nyaya or Neo-Logical darśana (school) of Indian philosophy was founded in the 13th century CE by the philosopher Gangesha Upadhyaya of Mithila. It was a development of the classical Nyaya darśana. Other influences on Navya-Nyaya were the work of earlier philosophers Vacaspati Miśra (900–980 CE) and Udayana (late 10th century).

Tattvacintamani dealt with all the important aspects of Indian philosophy, logic, set theory, and especially epistemology, which Gangeśa examined rigorously, developing and improving the Nyaya scheme, and offering examples. The results, especially his analysis of cognition, were taken up and used by other darśanas.

Navya-Nyaya developed a sophisticated language and conceptual scheme that allowed it to raise, analyse, and solve problems in logic and epistemology. It systematised all the Nyaya concepts into four main categories: sense or perception (pratyakşa), inference (anumana), comparison or similarity (upamana), and testimony (sound or word; śabda).

Indian logic attracted the attention of many Western scholars, and had an influence on pioneering 19th-century logicians such as Charles Babbage (1791-1871), Augustus De Morgan, and George Boole. George Boole (1815-1864) and Augustus De Morgan (1806-1871) make their pioneering applications of algebraic ideas to the formulation of logic (such as algebraic logic and Boolean logic).

Nasadiya Sukta, concerns the origin of the universe:

Who really knows?
Who will here proclaim it?
Whence was it produced? Whence is this creation?
The gods came afterwards, with the creation of this universe.
Who then knows whence it has arisen?
Socrates main contribution to Western philosophy is his method of inquiry that was called after him Socratic method, sometimes also known as elenchus. According to the latter, a statement can be considered true only if it cannot be proved wrong. Socrates believed that philosophy should achieve practical results for the greater well-being of society. He attempted to establish an ethical system based on human reason rather than doctrines. Socrates pointed out that human choice was motivated by the desire for happiness. Logic is the way that the mind operates. The mind reasons, either by way of valid thought or invalid thought. Aristotle's logic, especially his theory of the syllogism characterized by or capable of clear, sound reasoning logical logical definition: 1. using reason: 2. using reason: 3. reasonable and based on good judgment: something that is rational. Logical describes something that comes from clear reasoning. Using a fire extinguisher to put it out a fire is a logical step. Trying to put it out with gasoline is not. The best-known philosopher of the Navya-Nyaya, and the founder of the modern school of Indian logic, was Gangesha (13th century). The Nyaya school holds that there are four valid means of knowledge: perception (pratyaksha), inference (anumana), comparison (upamana), and sound, or testimony (shabda). Hinduism is a congregation of multitude of philosophies. Rather the essence of Hinduism is it's ability to question all it's own beliefs and customs. "athato Brahma jijnasa' or NOW we shall seek to understand the creator. Therefore to be a Hindu it is NOT required to agree or accept any belief systems or follow any rituals. Many rituals change from location to location, and even within a small sect of people in a particular location... rituals change from family to family.... Caste system is a social system and has NOTHING to do with any of the Hindu philosophies. So agreeing or disagreeing to the caste system has NO impact on being a Hindu. There are few thousand casts in HINDU society and the four varnas are general classifications. In conclusion from my side:- to be a Hindu. - It's NOT necessary to accept there is GOD (one can have healthy debate) - It's NOT necessary to 'believe' in any text or ritual - It's NOT necessary to fear God or be afraid of hell. - It's NOT necessary to identify with one of the varnas - which is normally stated as integral part of Hinduism is most introductions. - It's NOT necessary to be part of a caste (New converts to Hinduism in legal sense may not be part of any traditional caste). Hinduism takes phenomenal reality to be a projection of God (Brahman), who is both transcendent and immanent. In its transcendent form, Brahman is beyond any attributes; in its immanent form it may be visualized in many different ways, leading to a multiplicity of representations. The evolution of the universe is by laws (rita), yet sentient beings have freedom. The law of karma constrains ordinary action, but a realized person is free. The Vedic texts claim that language cannot describe reality completely, although its mystery may be experienced fully. Knowledge is classified in two ways: the lower or dual; and the higher or unified. The lower knowledge, which describes the objective world, is obtained using logic and it is accessible by language. The higher knowledge concerns the experiencing self and is beyond ordinary language. The seemingly irreconcilable worlds of the material and the conscious are aspects of the same transcendental reality. Hinduism is supportive of all scientific exploration, believing that at its end one becomes aware of its limitations and the need to reach the mystery of the experiencing self. From a personal perspective, Hinduism is concerned with techniques that make self-transformation possible. Hinduism thus endorses both science and technology although not necessarily in their modern forms or for distinctly modern reasons. Hinduism approaches the world in an ecological sense. Not only humans, but also animals, are conceived as sentient and, therefore, deserving of compassion. The Hindu approach to reality is through jnana (intuitive understanding) that includes subjective and objective knowledge, value and fact, and consciousness and reality. Jnana presupposes jijnasa, a reaching out to understand, that leads to a spark of illumination. Jnana requires the ethics of the individual as an indispensable condition for knowledge, which thus is not value free. Search for truth is a value orientation.

Comments on some Popular Statements

(1) Person who understands a book is a knowledgeable person, not the person who just owns the book.
(2) Librarian of a science library will not automatically become a Scientist. One has to learn Science to become a scientist
(3) What you know matters, not what your ancestors know!
(4) Acting like an expert or making an excellent presentation, does not make one an expert. Deceptive (giving an appearance or impression different from the true one; misleading)
(5) Your achievement is what you have learned or earned, not what you have inherited
  • Hinduism is like an ancient (thousands of years old), huge library with collections from many sources on many topics.

    But few are very old. Most of them are recent ones. All books in an library will not be there from first day.

  • Hinduism is a given name to collection of many faiths, by Greeks, Persians, etc. It is very ancient.

    Ancient Hinduism gave birth to many children saivam, vainavam, shakthism, buddhism, jainism etc. Now some of the children are grouped under old name Hinduism.

  • Hinduism has its roots in Nature worship.

    Many religions have started with nature worship. So all nature worships are not Hinduism.

  • Hinduism uses symbols and geometrical objects like cones, semi spheres, shivalingam.

    All symbols and similar shapes are not Hindu objects

  • Scriptures are written in sanskrit, tamil and many local languages.

    Languages are used to write non religious texts also. So, languages do not belong to religion (exclusive use).

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