PhD Student solves 2,500-year-old Sanskrit Grammar Problem

A PhD student from the University of Cambridge has solved a 2,500-year-old Sanskrit grammatical problem.

Twenty-seven-year-old Rishi Rajpopat decoded a rule taught by Panini, a master of the ancient Sanskrit language who lived around 2,500 years ago.

Sanskrit is mostly spoken in India by an estimated 25,000 people.

Rishi said he had “a eureka moment in Cambridge” after spending nine months “getting nowhere”.

He said: “I closed the books for a month and just enjoyed the summer – swimming, cycling, cooking, praying and meditating.

“Then, begrudgingly I went back to work, and, within minutes, as I turned the pages, these patterns started emerging, and it all started to make sense.”

Rishi explained he “would spend hours in the library including in the middle of the night”, but still needed to work for another two-and-a-half years on the problem.

Although it is not widely spoken, Sanskrit is the sacred language of Hinduism and over the centuries, it has been used in India’s science, philosophy, poetry and other secular literature.

Panini’s grammar, known as the Astadhyayi, relied on a system that functioned like an algorithm to turn the base and suffix of a word into grammatically correct words and sentences.

However, two or more of Panini’s rules often apply simultaneously, resulting in problems.

Panini taught a “metarule”, which is traditionally interpreted by scholars as meaning “in the event of a conflict between two rules of equal strength, the rule that comes later in the grammar’s serial order wins”.

However, this often led to grammatically incorrect results.

Rishi rejected the traditional interpretation of the metarule.

Instead, he argued that Panini meant that between rules applicable to the left and right sides of a word respectively, Panini wanted us to choose the rule applicable to the right side.

Using this interpretation, he found that Panini’s “language machine” produced grammatically correct words with almost no exceptions.

Rishi said:

“I hope this discovery will infuse students in India with confidence, pride and hope that they too can achieve great things.”

His supervisor at Cambridge, professor of Sanskrit Vincenzo Vergiani said:

“He has found an extraordinarily elegant solution to a problem which has perplexed scholars for centuries.

“This discovery will revolutionise the study of Sanskrit at a time when interest in the language is on the rise.”