《列子·仲尼》
而与南郭子隔墙为邻二十年，却从不互相拜访来往。在路上相遇时，也像没有看见对方一样。
而与南郭子连墙二十年，不相谒请；相遇于道，目若不相见者。
However, he lived next door to Nangongzi for twenty years, but they never visited or communicated with each other. When they met on the road, they always pretended not to see each other.