Don’t judge a book by its cover is a proverb. We will examine the meaning of the proverb don’t judge a book by its cover, where the expression came from, and some examples of its use in sentences.
Don’t judge a book by its cover is an admonishment to not judge someone or something simply on appearances; a proverb with a similar sentiment is appearances can be deceiving. The expression don’t judge a book by its cover, sometimes rendered as you can’t judge a book by its cover, is traced to the novel The Mill on the Floss, written by George Eliot in 1860. In the novel, the reference is to a physical book; within decades the expression came to be used metaphorically, though its popularity soared in the mid-20th century.
Examples
One of Marcus Rashford’s tattoos says ‘never judge a book by its cover’ and one should never judge a player off an international tournament. (Manchester Evening News)
“You have to meet him in person to know who he really is, you don’t judge a book by its cover.” (Sun News)
I think it’s just a really wonderful moment, if you do pick up on it as an audience member, to say wow, as cliche as it may sound, you can’t judge a book by its cover, and you need to take the time to understand and empathize. (Hollywood Reporter)