Gangesha Upadhyaya (late 12th century) was an India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

n mathematician

Mathematician

A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....

 and philosopher from the kingdom

Monarchy

A monarchy is a form of government in which the office of head of state is usually held until death or abdication and is often hereditary and includes a royal house. In some cases, the monarch is elected...

 of Mithila

Mithila

Mithila was a city in Ancient India, the capital of the Videha Kingdom. The name Mithila is also commonly used to refer to the Videha Kingdom itself, as well as to the modern-day territories that fall within the ancient boundaries of Videha...

. He established the Navya-Nyāya

Navya-Nyaya

The Navya-Nyāya or Neo-Logical darśana of Indian logic and Indian philosophy was founded in the 13th century CE by the philosopher Gangeśa Upādhyāya of Mithila. It was a development of the classical Nyāya darśana. Other influences on Navya-Nyāya were the work of earlier philosophers Vācaspati...

 ("New Logic") school. His Tattvacintāmaṇi (The Jewel of Thought on the Nature of Things) also known as Pramāṇacintāmaṇi (The Jewel of Thought on the Means of Valid Knowledge) is the basic text for all later developments. The logicians of this school were primarily interested in defining their terms and concepts related to non-binary logical categories.

Life

Gengesha was born at Karion village on the banks of the river Kamala, 19 km south-east of Darbhanga

Darbhanga

Darbhangā is a twin city and a municipal corporation and the capital city of the Darbhanga district and Darbhanga Division in the state of Bihar, India. It is one of the most important districts of North Bihar situated in the very heart of Mithilanchal. According to the latest 2011 census, the...

 in a Brahman

Brahman

In Hinduism, Brahman is the one supreme, universal Spirit that is the origin and support of the phenomenal universe. Brahman is sometimes referred to as the Absolute or Godhead which is the Divine Ground of all being...

 family. According to tradition, he was illiterate in his early years but later he acquired the knowledge of logic as a boon from the goddess Kali

Kali

' , also known as ' , is the Hindu goddess associated with power, shakti. The name Kali comes from kāla, which means black, time, death, lord of death, Shiva. Kali means "the black one". Since Shiva is called Kāla - the eternal time, Kālī, his consort, also means "Time" or "Death" . Hence, Kāli is...

. His son Vardhamana Upadhyaya was also a noted philosopher of the Nyaya school.

The Tattvacintāmaṇi

The text is divided into four khaṇḍas (books): Pratyakṣakhaṇḍa (book on perception), Anumānakhaṇḍa (book on inference), Upamānakhaṇḍa (book on comparison) and Śabdakhaṇḍa (book on verbal testimony). The first book opens with a salutation to Shiva

Shiva

Shiva is a major Hindu deity, and is the destroyer god or transformer among the Trimurti, the Hindu Trinity of the primary aspects of the divine. God Shiva is a yogi who has notice of everything that happens in the world and is the main aspect of life. Yet one with great power lives a life of a...

.