习非成是xí fēi chéng shì

对某些错误的说法或做法习惯了，反而认为它是正确的。也作“习非胜是”

例习乎习，以习非之胜是，况习是之胜非乎？——汉·扬雄《法官·学行》

英what becomes customary is accepted as right;