"most men - not only those considered clever, but even those who are very clever and capable of understanding most difficult scientific, mathematical, or philosophic, problems - can seldom discern even the simplest and most obvious truth if it be such as obliges them to admit the falsity of conclusions they have formed, perhaps with much difficulty -- conclusions of which they are proud, which they have taught to others, and on which they have built their lives." Leo Tolstoy.