《淮南子·泰族训》
人没有谁不知道学习是有好处的，但就是不去做，这是因为平时的嬉戏娱乐害成这样子。
人莫不知学之有益于己也，然而不能者，嘻戏害人也。
There is no one who does not know that studying is good, but they just do not do it. This is because their usual fun and entertainment has become this way.