He thinks he is a doctor, but a little learning is a dangerous thing.
a little learning is a dangerous thing
idiomPeople who don't understand something fully are dangerous
Origin
first recorded 18th c. disputed originFrom Alexander Pope's An Essay on Criticism (1711); often misquoted as 'a little knowledge'.
After watching one video, he tried to fix the electrical wires, forgetting that a little learning is a dangerous thing.
The manager warned the new staff that a little learning is a dangerous thing, especially when handling complex legal documents without proper training.
Last updated June 7, 2026