Over in the Game Rule Clarity thread, Jack Spencer Jr wrote:

Perhaps it would work if everyone played "please everyone else most?"

That would be great, but prone to catastrophe if not handled well. A game could utilize a "Do unto others as you would have them do unto you" approach, or a "reciprocal altruism" approach.

In the "reciprocal altruism" approach, players would try to please each other in hopes of some sort of valuable return, system-wise. If players are miserly when it comes to giving out rewards then they may find that no one cares to try and please them much anymore. Social reinforcement mechanics are just lovely.

In the "Do unto others" approach, the player would be tasked with trying to please the other players regardless of whether or not the other players responded in kind. Unless there is some solid mechanical structure that behooves players to focus on each others enjoyment this could lead to rampant abuse by less "group oriented" players. Once again, a simple social reinforcement mechanic involving the pleased player giving something valuable system-wise to the player that did the pleasing could probably go a long way to at least partly fulfilling the goal. The key here might be in making the given reward advantageous in the short-term, while giving a smaller long-term system benefit to turning down the reward.

You might know the following.

Torchbearer's sole reward mechanic works on reciprocal altruism alone. Each player, at the start of the game, holds a marker that signifies the privilege to bestow a reward. The reward consists of the marker (and its privilege) and a small shot of Resource; the bestower meanwhile gets an equal shot of Resource, but loses the reward privilege until another reward falls into his hands.

I haven't tested this, so I'm not sure it works, but the intention of the mechanic is that each player should be conscious of what the other players enjoy, and thereby produce happier play. It also directly punishes antisocial behavior through denial of an important Resource and of recognition as well.

C. Edwards wrote: A game could utilize a "Do unto others as you would have them do unto you" approach

In Doomchaser I have a social reinforcement mechanic that allows players to reward each other for reinforcing the setting and genre conventions in cool and interesting ways. This is basically a "you've pleased me in a particular way, according to the agreed upon terms" mechanic. There's a feedback loop in that the reward received gives the player greater ability to create those cool and interesting situations.

M. J. Young wrote: I'm not sure whether that's mechanically supported in any specific way, though; it's more like the game requires cooperative character and story creation, so that's got to be part of how it works.

In Gears & Spears, the tribe creation process (hopefully) encourages players to recognize the things they like to do and don't like to do in game and to give their tribe Virtues and Taboos accordingly. Since everyone is part of the same tribe, they must come to an agreement on their shared ethical code. Whatever the nature of their tribe's morality, virtuous acts are rewarded and taboos are punished through the use of an as-yet-undetermined resource. It's still undergoing revisions at the moment.