Cheng Pan-chiao says when flocks of birds--any birds--can find peace in the world by adapting themselves to the circumstances of the day (say, using rivers as their ponds), it should be a source of joy to man.
鄭板橋說，只要眾家鳥兒都能安心以天地為囿，江漢為池，各適其天，也就大快人心！