文学是未言之物的艺术。
——〈在广州农民运动讲习所第一届毕业礼演说〉,对讲习所学员发出警告,无法在中国发动阶级斗争,反之应该要用平和方法,以合作为诉求,1924年8月21日
To every action there is always opposed an equal reaction; or, the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.