- With a bronze mirror, one can see whether he is properly attired; with history as a mirror, one can understand the rise and fall of a nation; with men as a mirror, one can see whether he is right or wrong. Now I've lost my faithful mirror by the death of Weizheng.
- Quoted in: Yanqing Vanessa Ong et al. Memories unfolded: a guide to memories at Old Ford Factory, 2008, p. 50
- Quoted regarding his advisor.Few men in history would be so frank and honest with their monarch and when Weizheng died, Taizong was overwhelmed with grief. The Emperor said to his ministers,