I’ll come back to that. First, some notes on political economy.

When I try to understand political behavior, I, like many others, often find myself thinking about Mancur Olson’s classic The Logic of Collective Action. Olson’s simple yet profound insight was that political action on behalf of a group is, from the point of view of members of that group, a public good.

What do we mean by that? A public good is something that, if provided, benefits many people – but whoever provides it has no way to limit the benefits to himself or herself, and hence no way to cash in on the good’s provision. The classic example is a lighthouse that steers everyone away from shoals, whether or not they’ve paid the fee; public health measures that limit disease are in the same category. As a result, the fact that a public good is worth providing from society’s point of view is no guarantee that it will actually be provided; it has to be worth some individual’s while.

As Olson pointed out, the same goes for political action. Just because a political candidate’s victory would be good for, say, farmers doesn’t mean that farmers will give him or her money; each individual farmer will have an incentive to free ride on everyone else’s contributions. So political action is normally undertaken by individuals or small, organized groups that stand to benefit directly. Either that, or it’s a byproduct of other activities that are advantageous for their own reasons and can also be harnessed for political action, like memberships in trade associations or unions.

But don’t rich people give money to support the interests of their class? Actually, a lot of the money we see in politics ends up being money spent in the givers’ own, personal interests. For example, you can think of the Koch brothers’ political spending as an investment in themselves: they have benefited immensely from the recent tax cut, with a payoff that far exceeds the amount they spent promoting it.

So a lot of political action is driven by people trying to shape policy in a way that benefits them personally. But what the Shapiro/brain pills story drives home to me is that there’s another important factor in our current political scene: the use of political action as a marketing ploy, by people out to make a buck selling stuff that has little to do with politics per se.