followup to Violence
Everything has unintended, and often unpredictable, consequences. The side-effects of violence are almost never good. It can lead to feuding or to people avoiding dealing with the violent person. Provided you survive in the first place.
The best way to survive a fight is not to engage in one in the first place. No matter how good your skills, or how outnumbered your side has an opponent, you can still get killed. Your opponent is trying just as hard not to get killed as you are. And the confusion and "fog" in combat gives maximum opportunity for unknown factors to interfere (on both sides, the more numerous or skilled is still more likely to win). No matter how likely you are to win, you can still lose, or engage in mutual killing, you "win" the fight but still die afterwards. On the matter of fighting skills, consider the old adage, "The best swordsman in the world doesn't fear the second best, he fears the worst, because he can't predict what the silly son-of-a-bitch will do." (This particular wording of the quote, I have seen several equivalent versions, is from one of David Weber's Honor Harrington novels, I think from Honor of the Queen.)
The downside of avoiding fighting is a lack of deterrence. In the modern West, personal deterrence is less necessary because the criminal justice system provides a deterrent effect. Provided you avoid areas with concentrations of criminals,like many inner city neighborhoods. Also, personal deterrence is less useful, bordering on useless, where the aggressor is unlikely to know the victim. In general, though, "Violent crime is feasible only if its victims are cowards. A victim who fights back makes the whole business impractical." (Jeff Cooper, Principles of Personal Defense). Crime is a problem because most potential victims are cowards and incompetent.
Unless you are attacked, avoid combat, if you want a long, healthy life.
But if you are attacked, fight back.