Where did it say that? Ancient Confucians respected "sages", so in dynasties where Confucianism was dominant, "sages" were the exclusive preserve of Confucianism.
1. If it refers to Confucianism, it is probably: Yao, Shun, Yu, Tang, King Wen, King Wu, Confucius (the most holy), Yan Hui (the restored saint), Zengzi (the sage), Mencius (Ya Sheng). Strictly speaking, Yan Hui (restoration of saints), Zengzi (Zongsheng), and Mencius (sub-sage) are not considered "true saints", but "deputy saints".
In addition, if we count from Confucius onwards, they are all real historical figures. They are: Confucius, Yan Hui, Zengzi, Mencius, Zhu Xi, Wang Yangming, but there are less than ten.
2. If we combine the views of hundreds of schools of thought during the Spring and Autumn and Warring States periods, the ten ancient saints are: Three Sovereigns and Five Emperors, Confucius and Laozi. However, whether Lao Tzu in Taoism can be considered a saint is still controversial, because Taoism does not regard saints as the ultimate form of human beings, so they look down upon the title of "sage" (Taoism divides powerful people into three categories: saints, gods, and supreme beings, and even human beings). Highest).