Those people who think they know everything are a great annoyance to those of us who do.

The line is a pointed, self-undercutting joke about arrogance and intellectual posturing. It targets “know-it-alls” who claim total certainty, while the speaker ironically adopts the same stance (“those of us who do”), exposing how easily contempt for smugness can become smugness itself. Read this way, the quip works as both satire and caution: genuine knowledge is compatible with humility, curiosity, and revision, whereas the performance of omniscience tends to shut down conversation. The humor depends on the tension between expertise and overconfidence—suggesting that the real annoyance is not knowledge, but the refusal to acknowledge limits.

1) “People who think they know everything are a great annoyance to those of us who do.”
2) “Those who think they know it all are a great annoyance to those of us who do.”
3) “People who think they know everything are a great annoyance to those of us who know.”