《淮南子·俶真训》
外物不诱乱内在本性，那么本性就有安适的居所；性情保持平和，那么德就有安处的位置。
外不滑内，则性得其宜；性不动和，则德安其位。
If external things do not disturb the inner nature, then the nature will have a comfortable home; if the temperament remains peaceful, then the virtue will have a place to settle.