at 'The Hammock Papers' ...
"Being right all the time acquires a huge importance
in education, and there is this terror of being wrong.
The ego is so tied to being right that later on in life you
are reluctant to accept that you are ever wrong, because
you are defending not the idea but your self-esteem.
This terror of being wrong means that people have
enormous difficulties in changing ideas."
-Edward De Bono