"Mencius said that human nature is good. I disagree with that." — Xun Kuang

If there were no human nature, then there would be nothing for deliberate effort to be applied to. If there were no deliberate effort, then human nature would not be able to beautify itself.

Human nature and deliberate effort must unite, and then the reputation of the sage and the work of unifying all under Heaven are thereupon brought to completion.

Now it is human nature to want to eat to ones fill when hungry, to want to warm up when cold, to want to rest when tired. These all are a part of people's emotional nature.

In antiquity the sage kings recognized that men's nature is bad and that their tendencies were not being corrected and their lawlessness controlled.