Where did put on your thinking cap come from?

The phrase "put on your thinking cap" likely originated in the 19th century, referring to the idea of wearing a cap that enhances one's ability to think or concentrate. It evokes the image of a literal cap that one would don to signify the need for serious thought or problem-solving. The expression has since become a colloquial way to encourage someone to engage their intellect or creativity. Its use in educational settings helped popularize the phrase further.