Beginning in 213 BC, at the instigation of Li Si and to avoid scholars' comparisons of his reign with the past, Qin Shi Huang ordered most existing books to be burned with the exception of those on astrology, agriculture, medicine, divination, and the history of the State of Qin. This would also serve the purpose of furthering the ongoing reformation of the writing system by removing examples of obsolete scripts. Owning the "Book of Songs" or the "Classic of History" was to be punished especially severely. According to the later "Records of the Grand Historian", the following year Qin Shi Huang had some 460 scholars buried alive for owning the forbidden books. The emperor's oldest son Fusu criticised him for this act.