The Rational Optimist_ How Prosperity Evolves - Matt Ridley [82]
Ships of the desert
But the plundering, the lack of invention, the barbarians and above all Diocletian’s red tape did for Rome in the end. As the empire disintegrated under this bureaucratic burden, at least in the west, money lending at interest stopped and coins ceased to circulate so freely. In the Dark Ages that followed, because free trade became impossible, cities shrank, markets atrophied, merchants disappeared, literacy declined and – crudely speaking – once Goth, Hun and Vandal plundering had run its course, everybody had to go back to being self-sufficient again. Europe de-urbanised. Even Rome and Constantinople fell to a fraction of their former populations. Trade with Egypt and India largely dried up, especially once the Arabs took control of Alexandria, so that not only did oriental imports such as papyrus, spices and silk cease to appear, but those export-oriented plantations in Campania became the plots of subsistence farmers instead. In that sense, the decline of the Roman empire turned consumer traders back into subsistence peasants. The Dark Ages were a massive experiment in the back-to-the-land hippy lifestyle (without the trust fund): you ground your own corn, sheared your own sheep, cured your own leather and cut your own wood. Any pathetic surplus you generated was confiscated to support a monk, or maybe you could occasionally sell something to buy a metal tool off a part-time blacksmith. Otherwise, subsistence replaced specialisation.
This was never, of course, absolutely true. Within each village or monastery there was a degree of specialisation, but it was not enough to support large towns. At least there were now, as there had not been in slave-powered Rome, incentives to improve technology. A steady trickle of innovations began to improve productivity in northern Europe long after the end of the western empire: the barrel, soap, spoked wheels, the overshot water wheel, the horseshoe and the horse collar. Fitfully, Byzantium prospered from what was left of the Mediterranean trade, but plague, war, politics and piracy kept getting in the way. The predatory expansion of the Carolingian Franks in the eighth century, caused by a modest revival of regional trade in grain and manufactures, began also to stimulate trade in spices and slaves across the Mediterranean. The Vikings, paddling their boats down the rivers of Russia to the Black Sea and the Mediterranean, partly revived the oriental trade (with a little pillage thrown in) – hence their sudden prosperity and power.
But meanwhile the torch passed east. As Europe sank back into self-sufficiency, Arabia was discovering gains from trade. The sudden emergence of an all-conquering prophet in the middle of a desert in the seventh century is rather baffling as the tale is usually told – one of religious inspiration and military leadership. What is missing from the story is the economic reason that Arabs were suddenly in a position to carry all before them. Thanks to a newly perfected technology, the camel, the people of the Arabian Peninsula found themselves well placed to profit from trade between East and West. The camel caravans of Arabia were the source of the wealth that carried Muhammad and his followers to power. The camel had been domesticated several thousand years earlier, but it was in the early centuries AD that it was at last made into a reliable beast of burden. It could carry far more than a donkey could, go to places a wheeled bullock cart could not, and because it could find its own forage en route, its fuel costs were essentially zero – like a sailing ship. For a while even the Byzantine sailing ships of the Red Sea, waiting for the right winds and running the gauntlet of increasingly numerous pirates, found themselves at a competitive