Wang Bi
He Yan was not able to achieve political prominence either under Cao Pi or Cao Rui. When Cao Rui died in 239, he left his adopted son, Cao Fang, then still a child, on the throne. Cao Shuang, a relative of the Cao family, took control of the government as regent. He Yan ingratiated himself into Cao Shuang's inner circle, eventually being promoted to Secretary of Personnel () and bringing many of his friends and acquaintances into important positions. One of He Yan's friends promoted into office during this period was the influential philosopher Wang Bi.