Social Exchange
All social communication is actually transfer of "memes". (Memes are elements of know-how, which gets transferred from people to people, and undergo darwinian evolution by selection, and thus whole human cultures develop)
Memes were originally useful as primarily for exchange of survival tips, in both their raw and highly abstracted forms.
Today, with the relaxing of survival troubles, memes also have taken other secondary roles. Examples of such roles are generating happiness (which may or may not directly relate with survival), ways for producing fun, and satisfaction of other not-directly-for-survival desires.
People act like a bag of memes. They collect and retain memes of their choice, useful for their own ends. Then they tend to be friends with people who can be the source of their most desired memes.
In fact, society can be viewed as a huge marketplace of memes. People advertize and sell their memes, and gain social currency in doing that. The more desirable memes a person, the more is the demand for that person, the more socially rich he is.
This concept provides for a consistent way of looking at a large part of the working of society.
"He is fun", tells one about another. What does that mean? He has the memes that can give you fun, so go and get some of them from him! So that you can then spread some of them to yet others.
Here I assume that memes are behavior-generating elements as well, since behavior is very much a result of his past experience, and his experience can be imagined as consisting of memes or as producing behavior which can generate memes).
[Fun is required for a person's psych in order for him to be happy and want to live, thus increasing survival duration.]
This is the way the social transaction of memes takes place.
Notably, the most popularly exchanged kind of memes differ in different cultures and communities. For example, in under-developed and developing countries, the most exchanged memes are those more closely related to survival in a biological and social sense. People want to know ways they could find efficient ways of utilizing resources, ways they could create a new business that would earn them livelihood, ways they could be happy in deteriorating circumstances by following spirituality or some such, etc. In developed countries, simply-fun-n-cool type of memes are more desired for. People want to know what are ways to get new cool music (Kazaa), has Tom Cruise has yet come out with some new cool movie, some cool place to hike and camp, etc. This might actually cause some people to be not very "functional" (functional means capable of finding best ways to for self-survival), since coolness does not always correlate very well with basic survival.
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