It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so

Proposed by a contributor, not yet supported by evidence.

Meaning · English

Misconceptions can cause more problems than lack of knowledge

Nghĩa · Tiếng Việt

Những hiểu lầm có thể gây ra nhiều vấn đề hơn là thiếu kiến thức

Machine-translated — suggest a fix

Where it’s used: Used Widespread English
Sources & notes

Listed on Wikipedia “List of proverbial phrases” (CC BY-SA 4.0, retrieved 2026-07-29); definition pending editorial review. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-30; pending editor spot-check.

Common questions

What does “It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so” mean?

Misconceptions can cause more problems than lack of knowledge

Is “It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.