The difference between wise and clever

I think there is some truth to this - from Dan Galvin's Thought For The Day mailing list:

You can tell whether a man is clever by his answers.
You can tell whether a man is wise by his questions.
                         -Naguib Mahfouz,
                          writer, Nobel laureate
                          (1911-2006)
                          Quoted in A.Word.A.Day