He comes from a cultured family: his father Jirō Nitta and mother Tei Fujiwara were both popular authors. He graduated from the University of Tokyo in 1966. He began writing after a two-year position as associate professor at the University of Colorado, with a book Wakaki sugakusha no Amerika designed to explain American campus life to Japanese people. He also wrote about the University of Cambridge, after a year's visit (Harukanaru Kenburijji: Ichi sugakusha no Igirisu). In a popular book on mathematics, he categorized theorems as beautiful theorems or ugly theorems. He is also known in Japan for speaking out against government reforms in secondary education. He wrote The Dignity of a State, which according to Time Asia was the second best selling book in the first six months of 2006 in Japan . In 2006 he published Yo ni mo utsukushii sugaku nyumon ("An Introduction to the World's Most Elegant Mathematics") with the writer Yoko Ogawa: it is a dialogue between novelist and mathematician on the extraordinary beauty of numbers.
His 2005 book "Dignity of the State" has been criticized as racist and deliberately echoes a notorious pamphlet issued by the Japanese government in 1937, at the peak of nationalist hysteria, in an attempt to define the essence and superiority of Japanese culture. The pamphlet (Essence of the National Polity) is notorious for clearly setting out the basis on which Japan's ultra-nationalists claimed racial superiority over the rest of mankind.