To doubt one's own first principles is the mark of a civilized man. Don't defend past actions; what is right today may be wrong tomorrow. Don't be consistent; consistency is the refuge of fools.
Hyman RickoverAs a guide to engineering ethics, I should like to commend to you a liberal adaptation of the injunction contained in the oath of Hippocrates that the professional man do nothing that will harm his client.
Hyman Rickover