What is "zengzi"

Zengzi (, 505–435 BC), born Zeng Shen or Zeng Can , courtesy name Ziyu , was an influential Chinese philosopher and disciple of Confucius. He later taught Zisi (Kong Ji), the grandson of Confucius, who was in turn the teacher of Mencius, thus beginning a line of transmitters of orthodox Confucian traditions. He is revered as one of the Four Sages of Confucianism.