The research target of the book is Zhang Dongsun, Professor of Yenching University, Wang Yunsheng, chief editor of Ta Kung Pao and Pan Guangdan, Professor of Tsinghua University respectively. In 1949 all three had outstanding achievements in different areas, but they took a plunge after 1949 and their career never recovered. Professor Yang Kuisong is unsatisfied with asking general questions had asked in the past such as why intellectuals in Chinese mainland could even stop thinking in that year and make a collective diversion. Because of the disclosure of more and more private records, a variety of newspapers, and archival documents, Yang Kuisong will focus first on the changes of the intellectuals’ fate in the new China and then try to explain and understand their recognition of the great time changes, as well as the actions taken. He tries to find out the intellectuals’ mentality from the historical background and environment.