Markets are more and more anonymous. While computers trade with each other many times a second, most transactions still occur because a human being makes a decision to trade. But there are many such people, and they need not disclose who they are.

Uncomfortable with this depersonalisation, we use phrases such as “the market thinks” or “we could ask the market”. Benjamin Graham, the father of value investing, came up with “Mr Market”, a moody individual whose occasional irrational optimism and unreasoning pessimism create trading opportunities. But there is no Mr Market: only people can think.

The anonymity of markets delights the political right, which welcomes it as a check on state authority, just as it infuriates the political left, which deplores the freedom of the market from democratic control. Monetary policy – a market-based policy favoured by the right – restricts spending by price through the discipline of higher interest rates. Fiscal policy, favoured by the left, requires political choices about levels of taxation and public spending. Similarly, in a healthcare market, provision is rationed by price, impersonally; whereas socialised medicine (like private insurance) rations by bureaucratic decision, whether through waiting lists for treatment, or the cost-benefit analyses of the UK's National Institute for Clinical Excellence.