It might seem from what I’ve said so far that wealth depends purely on people producing goods and services. But they don’t do it on their own, from scratch, but mainly by using and building on what’s already been produced, on what today’s society inherits from yesterday’s, and by drawing upon nature’s resources. This is our common inheritance – or simply ‘the commons’.

Compare today’s earnings now with those of people in the 19th century; workers today are of course much better off. But this is not because they are working any harder or are more deserving than their ancestors. They are producing far more output for each hour they work – in the US, output per person per hour is estimated to have increased 15-fold since 1870 – but that’s because they are working with better technology, in better-organised workplaces, in a society with faster communication and distribution systems. So the difference in wealth is a result of society as a whole being more productive. The accumulated intelligence, know-how and investments of successive generations are what have made us so productive now. Without them we would be desperately poor. Yet we so easily fail to notice our enormous debts to the past and imagine that our pay is simply a reflection of our personal merit and effort or contribution. Some of this inheritance may be privatised by a minority – and not the ones who created it! – with far-reaching implications for the production and distribution of wealth, but I’ll come to that in a bit.

Most of what we so easily attribute to our own intelligence and efforts is the hard-won product of previous generations’ thought and labour, to which any one of us can rarely add more than a little. Indeed, the more this inheritance grows, the smaller our additions in proportion to it. In their important book, Unjust Deserts, Gar Alperovitz and Lew Daly quote this halting challenge from the Bible: