Jo also believed that any talented people including slaves should be appointed as officials regardless of social status. He was said to judge people by moral character and did not greet superior officials if he considered them of unworthy characters while he was courteous even to his servants. For instance, he formed a friendship with a butcher/tanner of lowest class (baekjeong) who did not even have a name and admired his learning so much that he discussed state affairs with him and wanted to appoint him as a court official. But the tanner repeatedly refused Jo's offer and then disappeared without a trace according to Records of Yeonryeoshil (연려실기술), a collection of official and unofficial history books compiled by Yi Geung-ik in late Joseon Dynasty. (It is said that King Injong, Jungjong's successor who admired his tutor Jo Gwangjo, listed the "tanner" as Chief State Councillor for his future cabinet for he was greatly admired by Jo.) According to famous Korean philosopher Yi I, Jo was admired so much by populace that when he appeared on streets people gathered before him saying, "Our master is coming."