What is the slogan of that book on the bus?

Seek truth from facts and practice benevolence and righteousness.

The slogan put forward by Kang Youwei and Liang Qichao and other reformers when they jointly wrote to Emperor Guangxu on the bus. Call on the emperor to carry out pragmatic education and advocate the practice of moral ethics and benevolence and morality. This event had a far-reaching impact on China's modern ideological movement and political reform, and became one of the important historical events in the process of China's modernization.