| 1 | Therefore, he was refuted by Ruan Yuan in the Han-Song Controversy. | |
| 2 | Otherwise, Li' ao' s theory of human nature didn' t leave nothing to be desired. It couldn' t answer the difficult questions of itself , but with the brand of the landlord class in the feudal society. | |
| 3 | However, it contains the contradiction of good producing evil, which gave rise to the dualism of nature from ZHANG Zai to ZHU Xi, a relatively perfect solution to LIs problem. |