Some of us here at the Duck would put ourselves into the “relational” camp when it comes to how we approach Social Science. Among other things, this approach looks at social and political actors based on their relations to other actors and position within a social network rather than as autonomous entities.

Dan’s work, for example, has made excellent use of social network theory to talk about empires and such.

Today’s Washington Post points out that

a growing body of evidence is suggesting that traditional social networks play a surprisingly powerful and underrecognized role in influencing how people behave.

In particular, a team of researchers has found that social networks strongly influence your health, with profound personal and political consequences:

obesity appeared to spread from one person to another through social networks, almost like a virus or a fad.

In a follow-up to that provocative research, the team has produced similar findings about another major health issue: smoking. In a study published last week in the New England Journal of Medicine, the team found that a person’s decision to kick the habit is strongly affected by whether other people in their social network quit — even people they do not know. And, surprisingly, entire networks of smokers appear to quit virtually simultaneously.

Taken together, these studies and others are fueling a growing recognition that many behaviors are swayed by social networks in ways that have not been fully understood. And it may be possible, the researchers say, to harness the power of these networks for many purposes, such as encouraging safe sex, getting more people to exercise or even fighting crime.

“What all these studies do is force us to start to kind of rethink our mental model of how we behave,” said Duncan Watts, a Columbia University sociologist. “Public policy in general treats people as if they are sort of atomized individuals and puts policies in place to try to get them to stop smoking, eat right, start exercising or make better decisions about retirement, et cetera. What we see in this research is that we are missing a lot of what is happening if we think only that way.”