Everybody has a secret, and someone who knows what it is. Don't trust your school teacher. Don't trust your clergy. Shovels are for more than digging holes. A lucky pen is not lucky at all.
Conscience is just a fear of getting caught.
No conscience is better than some conscience. Angels in white are not as benevolent as they seem. A good loser is still a loser. Never accept a favor, the price will be too high. If you witness a crime, find a way to profit from it.