This is the most important thing I will ever say to you. The human mind is the ultimate testing device. You can take all the notes you want on the technical data, anything you forget you can look up again, but this must be engraved on your hearts in letters of fire. There is nothing, nothing, nothing, more important to me in the men and women I train than their absolute personal integrity. Whether you function as welders or inspectors, the laws of physics are implacable lie detectors. You may fool men. You will never fool metal. That's all.
Lois McMaster Bujold