all cats are grey in the dark
暗中看來，所有的貓都是灰色的
書面語·比喻外表差異被忽略
英文釋義
when it is not possible to see or perceive differences, appearances or distinctions become irrelevant
例句
In the dim light of the club, all cats are grey in the dark, so I couldn't tell who was who.
典故來源
源自古老諺語，強調在黑暗中無法區分顏色或特征，比喻外表差異在特定條件下無關緊要。