Literal meaning

cover (掩) — ear (耳) — steal (盗) — bell (铃)

Origin

Lüshi Chunqiu (《吕氏春秋·自知》). A thief tried to steal a large bell. It was too heavy to carry, so he tried to break it into pieces — but every blow made the bell ring loudly. Terrified of being heard, he covered his own ears, thinking that if HE couldn't hear it, no one else could either. The story is the canonical example of self-deception so obvious that it's comical — and yet, as the text points out, it's a pattern people repeat constantly.

Examples

Usage & nuances

Sharply critical of denial. Common in news editorials about institutional or corporate self-deception. Slightly less common in personal contexts because it's pointed.