Intergalactic idea sex

In The Rational Optimist, I argue that the human technological and economic take-off derives from the invention of exchange and specialisation some time before 100,000 years ago. When people began to trade things, ideas could meet and mate, with the result that a sort of collective brain could form, far more powerful than individual brains. Cumulative technology could begin to embody this collective intelligence.

Of course, I did not invent this idea. In keeping with the theory, I merely put together the ideas of others, notably those of Joe Henrich (collective intelligence), Rob Boyd (cumulative culture), Paul Romer (combinatorial ideas), Haim Ofek (the invention of exchange) and many others.

There was also the important thought that came from Adam Powell, Stephen Shennan and Mark Thomas, namely that temporary `outbreaks' of new technology in Paleolithic Africa probably have a demographic explanation. That is, when population density rose, it resulted in a spurt of innovation; when population density fell, it resulted in technological regress (as happened in Tasmania when it was isolated). Technology was sophisticated, in other words, in proportion to the number of people networked by exchange to sustain and develop it.

By this interpretation, animals with plenty of culture but no habit of exchange and specialisation between groups -- killer whales, chimpanzees, crows, Neanderthals -- do not experience headlong technological and economic `progress', however clever they get.

Michelle Kline and Rob Boyd have since produced evidence from Pacific islands that technological complexity correlates with population size (and contact with other islands):

In Oceania, around the time of early European contact, islands with small populations had less complicated marine foraging technology. This finding suggests that explanations of existing cultural variation based on optimality models alone are incomplete because demography plays an important role in generating cumulative cultural adaptation. It also indicates that hominin populations with similar cognitive abilities may leave very different archaeological records, a conclusion that has important implications for our understanding of the origin of anatomically modern humans and their evolved psychology.

Now comes a new thought from a completely different direction. A Russian and a Ukrainian scientist have been modelling the universe to  understand what happens when civilisations from different planets meet (hat tip Marc Merlin). Technology Review takes up the tale:

The parameters that govern the evolution of this universe are simple: the probability of a civilisation forming, the usual lifespan of such a civilisation and the extra bonus time civilisations get when they meet.

The result gives a new insight into the Fermi Paradox. Bezsudnov and Snarskii say that for certain values of these parameters, the universe undergoes a phase change from one in which civilisations tend not to meet and spread into one in which the entire universe tends to become civilised as different groups meet and spread.

Of course, it is only a model. That is to say, Bezsudnov and Snarskii assume the conditions that lead to their conclusion:

We assume, that the unique reason which can prolong a lifetime of the Civilization, is the contact to other Civilizations. The meeting of Civilizations generates the new purposes and objects of knowledge, necessity to use an Intellect.

They have not proved, for example, why civilisations must die after a certain time if they don't meet others. But the description of isolated interstellar civilisations eventually and explosively linking up and `globalising' is a pretty good description of what happened on planet earth over the past 100,000 years:

It is shown that there exists a scenario when at the given moment almost all Civilizations are lonely– ``there is nothing'', however after some, sufficiently prolong time Civilizations will get into a contact and the Universe as a whole becomes civilized. Conclusion is that it is necessary to wait!

That's an exciting thought with which to go off on holiday. Back in mid August.