<human>:  Who was the real life person that the book, ‘The Man Who Knew Infinity’, is based on?
<bot>: The book is based on the life of Srinivasa Ramanujan. Ramanujan was an Indian mathematician and philosopher who lived in the late 19th century. He made many contributions to number theory and was the first to prove many famous mathematical conjectures. Ramanujan's work was largely unknown until the publication of the book in the 1920s.