integrity

Definition:  The quality of being honest and having strong moral principles; moral uprightness.
Synonym’s:  Honesty, probity, rectitude, honor, good character, principle(s), ethics, morals, righteousness, morality, virtue, decency, fairness, scrupulousness, sincerity, truthfulness, trustworthiness
Example: when someone loses his wallet and you return it without even looking at its inside means that you have integrity.