Is there any necessary connection between our actions and the happiness of others? Disregarding for a moment the murkiness of the definitions of "actions" in philosophical literature - two types of answers were hitherto provided.

Sentient Beings (referred to, in this essay, as "Humans" or "persons") seem either to limit each other - or to enhance each other's actions. Mutual limitation is, for instance, evident in game theory. It deals with decision outcomes when all the rational "players" are fully aware of both the outcomes of their actions and of what they prefer these outcomes to be. They are also fully informed about the other players: they know that they are rational, too, for instance. This, of course, is a very farfetched idealization. A state of unbounded information is nowhere and never to be found. Still, in most cases, the players settle down to one of the Nash equilibria solutions. Their actions are constrained by the existence of the others.

The "Hidden Hand" of Adam Smith (which, among other things, benignly and optimally regulates the market and the price mechanisms) - is also a "mutually limiting" model. Numerous single participants strive to maximize their (economic and financial) outcomes - and end up merely optimizing them. The reason lies in the existence of others within the "market". Again, they are constrained by other people