In the geo-scientific process of reconstruction of the Jiulong River of Ming Dynasty，the author found that the real “Killing Curse” of Jiulong River flood was the coupling result of various factors，such as climate，regional topography，astronomical tide，storm surge and the distribution of water systems，etc. which was irrelevant with the reconstruction of South Gate bridge in Zhangzhou. However，when the “local saints” Chen Chun questioned the reasonableness of the site of South Gate bridge，the saying-killing of South Gate Bridge，had been kidnapped by his enormous influence since the Southern Song Dynasty，so that the Records in Ming and Qing Dynasty protected the saying in every possible way. For Zhangzhou South Gate Bridge，local records were convinced of Chen Chun’s remarks rather than delve into the truth of the killing flood. At best，the saying could fool the people who were unaware of the truth only. It wouldn’t cause more serious consequences，because the South Gate Bridge wasn’t the culprit at all. However，once such “superstition” became the intellectuals’ mainstream values，it would kill people’s desire to pursue the truth from the spiritual level. This was not only completely contrary to the spirit of exploring the truth of nature in modern geo-science，but also restricted the origination and development of modern geo-science in traditional China.