It is one thing to show a man that he has erred, but quite another to put him in possession of the truth. Oh, what a tangled web we weave, when first we practice to deceive. Unlike grownups, children have little need to deceive themselves. There is great skill involved in knowing how to conceal one's skill. Suspect him the most who trusts the least.
Nothing is more damaging to a new truth than an old error.
Unwavering convictions can be a more dangerous foe of truth than lies. Crafty people deal only in generalizations. We find it so easy to believe that praise is sincere.