The first casualty of war is said to be the truth but, in financial crises, it is trust that dies. While the after-effects of the recent crisis are constantly debated, this deeper issue remains unaddressed.

Paul Seabright, a professor at the Toulouse School of Economics, has identified traits that underpin social systems such as money: the capacity to weigh up the costs and benefits of trusting others, and the instinct to return favours in kind or seek revenge when trust is betrayed. When it is working well, the system enables strangers to safely deal with each other. However, this fragile system, on which the global economy depends, is now at risk of failing.

Money, a mechanism of exchange and a store of value, galvanised modern economies. Debasement of currencies through quantitative easing and artificially low interest rates undermine these functions.