This paper was the result of the above-mentioned work of Zhu and Cao, which Yau promoted in the Beijing conference. "The New Yorker" article concludes by linking the alleged actions of Yau with Perelman's withdrawal from the mathematical community, stating that Perelman claimed not to see "what new contribution and Zhu did make"; that he had become disillusioned by the lax ethical standards of the community. As for Yau, Perelman is quoted saying, “I can’t say I’m outraged. Other people do worse. Of course, there are many mathematicians who are more or less honest. But almost all of them are conformists. They are more or less honest, but they tolerate those who are not honest”.