I would like to put this quote from Daniel J. Boosting, an American historian who was the twelfth librarian of the United States Congress, somewhere where I see it regularly.
The greatest obstacle to discovery is not ignorance—it is the illusion of knowledge.
“I know.” I need to catch myself when I say this simple phrase. It signals that I am closed. Once I think I know then I am no longer seeing with wonder or looking for new details. I’m taking something for granted.
Years ago I read that a student who was taking an art class was having great difficulty drawing the objects they were to draw and was thinking about dropping out. He talked to the teacher after class, and the teacher asked him to try one more time. So he went back to his easel, and the teacher set up some objects at the centre of the room as usual, but this time when everything was set he threw a sheet over them and asked the student to draw what he saw. So the student drew the shapes that he saw under the sheet, and when he was done and the sheet was removed he realized that he had drawn the forms much better when they were just shapes, when he didn’t know they were apples and vases.
I don’t know if this is a true story or not, but it always stuck with me. Thinking we know something often stops us from seeing it.