all cats are gray in the dark

proverb In the dark of night, appearances do not matter (because it is too difficult to see anything clearly). A: "I can't believe you're going on a date with someone you've never met before! What if you don't think he's attractive?" B: "Eh, all cats are gray in the dark—it will be fine." You really need to give the house a fresh paint job. I know that all cats are gray in the dark, but prospective buyers will be looking at this house during the day! A: "Do you really think he's going to bring some random girl home from the bar?" B: "Well, he's drunk, he's lonely, and all cats are gray in the dark, so I'm thinking yes."

Prov. When in the dark, appearances are meaningless, since everything is hard to see or unseen. I don't care if my date is ugly. All cats are gray in the dark.