As Kermit Roosevelt (huh?!) mentions in the American Prospect,  former Supreme Court Justice Sandra Day O'Connor is said to have had an embroidered cushion in her office that read “Maybe in error, but never in doubt”.

If that rings a bell,  here is a hint:

Once the decision has been made, to shut your ears even to the best counter-arguments: a sign of a strong character. Also an occasional will to stupidity.

That is of course from Nietzsche (Beyond Good and Evil).