Debora MacKenzie wonders whether politicians could learn how to keep the peace from epidemiologists

July 2, 2005 New Scientist

…In the June issue of PLoS Biology, Paul Ehrlich and Simon Levin of Stanford University in California have called for evolutionists, behavioural biologists and ecologists to start trying harder to model human cultural evolution. Useful models have so far eluded scientists. In particular, they say, we need to understand what controls the development of social “norms” which, among other things, govern war. The model they suggest is disease.

Richard Dawkins famously proposed the idea of the meme as a unit of cultural evolution, as the gene is for biological evolution. But Ehrlich and Levin say we have gained little understanding from trying to model memes as though they were genes. The two are just too different, they say: memes spread up, down and sideways in a population, not just from parent to offspring. They are impermanent. They vary enormously and quickly.

Yet that is exactly how pathogens behave. Like pathogens, ideas must infect a critical number of people before an epidemic starts. Some hosts are more susceptible than others. There are threshold phenomena, and superspreaders.

Similar ideas, Levin told me, were explored in The Tipping Point, writer Malcolm Gladwell’s bestseller of 2000, which used psychological research to show how fads and cultural norms spread much like diseaseì– the “tipping point” being the critical threshold of some event that triggers an epidemic. All these ideas seem sensible enough to make you wish a hard-nosed experimental epidemiologist would get to grips with them.

Because if ideas can spread like epidemics, then epidemiological understanding may suggest controls. The idea of launching a war, for example, reaches its tipping point when it has infected enough of the right people. After that point, it can become unstoppable. Could there be some way of recognising where those epidemic thresholds are and interfering, by launching counter-ideas among the right people in the same way that doctors launch vaccine drives against disease?

But pursue the analogy. We have a vaccine against the kinds of viruses most likely to cause the next flu pandemic, but it seems unlikely that we will be able to administer it in time to make much difference. If we ever develop a war vaccine, who will administer it?