Where has Mayconomics come from? A few commentators have called it a version of Milibandism, but it seems more likely that Mrs May has been reading not only Adam Smith’s Wealth of Nations, but also his Theory of Moral Sentiments, in which he compared two attitudes to government: first, a "public spirit" that was founded upon the love of humanity and a desire to prevent hardship, and second a "spirit of system". The "man of system", Smith said, was "apt to be very wise in his own conceit; and is often so enamoured with the supposed beauty of his own ideal plan of government, that he cannot suffer the smallest deviation from any part of it."

"He seems to imagine that he can arrange the different members of a great society with as much ease as the hand arranges the different pieces upon a chess board. He does not consider that in the great chess board of human society, every single piece has a principle of motion of its own, altogether different from that which the legislature might choose to impress upon it."

Many economists today are in thrall to this spirit of system. They live in an abstract world in which the equations always work out. They believe that in a market economy people will always be better off, and when they are not they refuse to face facts. This attitude has been called the "Davos lie" by former US Treasury Secretary, Larry Summers, and looking back we can see that Ronald Reagan was making the same point when he gently ribbed those economists who argued that what worked in practice could not possibly work in theory. It looks as if Mayconomics is a pragmatic approach that recognises that freedom is a political achievement, not the absence of government, and that free enterprise requires active government not the minimal state.