Final answer:
Xunzi taught that humans are innately evil and must be closely controlled through self-cultivation and external guidance.
Step-by-step explanation:
According to the information provided, the man who taught that humans are innately evil and must be closely controlled is Xunzi. Xunzi was a later Confucian teacher who believed that humans have an innately detestable nature but can become good through deliberate action and self-cultivation. He emphasized the importance of external forces such as rituals and teachings to guide human behavior.