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.

Often attributed to Mark Twain or Yogi Berra

Variant: The trouble is not what we don't know, it's what you know for sure that just ain't so.

Anonymous Quotes

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.

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.

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.

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.