I heard once that your conscience is like a sharp block in your chest. Each time you do something that troubles your sense of decency, or morality, if you will, that block spins around, creating a painful sensation which is impossible to ignore. However, if you can train yourself to ignore the discomfort long enough, you can wear the edges of that block so smooth that it spins like a cue ball, causing little sensation at all. It’s at this point you can pardon yourself.