What kind of rules should govern our lives? I'd argue that the best rules are those that we'd be satisfied with if our very worst enemy were in charge of decision-making. The foundation for such rules was laid out by my mother. Let's look at it.
My mother worked as a domestic servant. That meant that my younger sister and I often lunched at home by ourselves during our preteen years. Being bigger and stronger than my sister, I seldom divided the food evenly, especially the desserts. After a tiring day at work, Mom would be greeted by sob stories from my sister about my lunchtime injustices. Mom finally became fed up with the sibling hassles. She didn't admonish me to be more caring, fair, sensitive and considerate. She just made a rule: Whoever cuts the cake (pie, bread, meat, etc.) allows the other the first selection. With that new rule in place, you can bet that when either my sister or I divided food, it was divided equally.
You say, "That's a nice story, Williams, but what's the point?" The point is that the principle underlying Mom's rule is precisely the kind that is necessary for rules to promote fairness. In general, the rules that we should want are those that promote fairness, whether it's our best friend or it's our worst enemy who's the decision-maker. In the case of Mom's rule, it didn't make any difference whether I hated my sister's guts that day or she hated mine or whether my sister was doing the cutting or I was; there was a just division of the food.
Think for a moment about rules in sports, say basketball. One team loses, and the other wins, but they and their fans leave the stadium peacefully and most often as friends. Why? The game's outcome is seen as fair because there are fixed, known, neutral rules evenly applied by the referees. The referees' job is to apply the rules -- not determine the game's outcome. Imagine the chaos and animosity among players and fans if one team paid referees to help it win or the referees were trying to promote some kind of equality among teams.