1
the best and most beautiful things in the world cannot be seen nor even touched, but just felt in the heart
Attribution contested
The words are Keller's, but two things in the popular version are not. The wording is smoothed -- it usually appears as they must be felt with the heart -- and, more importantly, Keller does not present the thought as her own: she writes that her teacher explained it to her. On her own account the sentence belongs at least as much to Anne Sullivan.