The stupid neither forgive or forget; the naive forgive and forget; the wise forgive but do not forget. — Thomas Szasz. Hungarian-American psychiatrist and activist (1920–2012)
Every act of conscious learning requires the willingness to suffer an injury to one's self-esteem. That is why young children, before they are aware of their own self-importance, learn so easily; and why older persons, especially if vain or important, cannot learn at all.
Formerly, when religion was strong and science weak, men mistook magic for medicine; now, when science is strong and religion weak, men mistake medicine for magic.
A child becomes an adult when he realizes that he has a right not only to be right but also to be wrong.