The skill, ability, or wisdom to avoid conflict and choose what is right and what is good or beneficial to humanity.
Be cordial. When you approach, communicate, talk to or listen to an individual you do not like, use good judgment and discipline yourself to use reason vs emotion. Your judgment may dictate that the individual you are conversing or dealing with is totally disagreeable, offensive, vile and revolting yet you need to rise above all that negative emotion and use reason to be gracious, hospitable, warm and friendly. Diplomacy requires prudence. Be attentive and listen more to what others are saying or just simply talking about. Always speak the truth, but avoid excessive deliberations, otherwise folly will be your company. You can't be diplomatic without being prudent. Being prudent however, does not imply that one has to be submissive to the bully or evil.