Technology improves everything: at any rate, it increases efficiency and improves quality. Education is no exception; it too has been transformed by technology. When I was young, one was supposed to learn from human teachers standing in front of students and talking. Once in a while they might turn their backs on students and write on the board; and if they found students talking behind their backs, they might make them stand up or send them out of the class. They were supposed to take the students through textbooks.

That is how it was in school. But teaching was different in Cambridge. There, teachers trained students to become economists - that is, to think, argue, read, write and speak economics. They did so by making students answer economic questions in a weekly essay, and then making them defend their answers. It was teaching by example.

Some decades later came internet; it brought a flood of literature online. Face-to-face lectures were no longer necessary; they could be uploaded on internet. But learning from good economists was still valuable. In Stanford, which I visited some 15 years ago, lectures were a variant of supervisions in Cambridge 60 years ago. Teachers came to a lecture room, students would come in, there would be questions, arguments, and pointers to literature. Students did not have to attend lectures; teachers had to attract students with their brilliance and entertainment. A good economist was a star actor.

Another difference between more traditional Indo-British universities and American universities was the structure of a degree. In the former, teachers defined what students had to learn to become economists; in the latter, students were offered considerable choice of courses, and only had to pass a minimum number to get a degree. There was thus competition not just between economists, but also between academics in different subjects to attract students. As a result, the student market - which itself was shaped by the job market - determined over time what subjects should expand and contract.

If the job market determined the structure of subjects taught, it was inevitable that teachers would seek to develop markets outside universities. Economists did not have to do that; a market for them was already there in businesses and government. But they could raise their market exposure by means of publicity - by writing books, appearing on television programmes, and writing articles and blogs. They could create markets for themselves.

I adapted myself to the market; I did more than a dozen jobs involving teaching, research, organization, journalism etc. My friend, Ashok Guha, on the other hand, devoted himself to teaching; he was one of the best in the field. But times have changed. A generation ago, a career and a lifetime were more or less the same; people did not live much beyond retirement, and when they did, they were kept busy by family duties, nurture of grandchildren, and health concerns. Now, however, this second career often does not suffice. An economist cannot stop thinking economics on crossing into his seventies.

So Ashok Guha has tried his hand at something new: he has written a book to make economics entertaining for people who never took any interest in it. He poses questions and tells some stories that even I found riveting.

Historically, farms that grow subsistence goods like food grains are small - generally just large enough for a family to manage. Plantations, on the other hand, are large, for instance, tea gardens or coffee estates. This is because farm operations are such that it is impossible to identify the work done by any individual, except in harvesting. In plantations, however, it is easy to measure the tea or coffee plucked by a worker. Then plantation workers can be paid on the basis of their output, whereas farm workers' work has to be watched and supervised. That is Ashok Guha's explanation of the relative size of farms and plantations: plantations require less of laborious supervision.

I also found his questioning of received economics fascinating. Something that macroeconomists unthinkingly do is to use figures of national income and its variants to make judgments about whether people are better off. Easterlin pointed out the lack of correlation between per capita income and indicators of happiness. Ashok Guha shows that more people kill themselves in prosperous countries. Amartya Sen was dissatisfied with the material standard of living as a measure of happiness; his unhappiness led to the development of the human development index, which brought in education and longevity. His criteria led to the identification of Kerala as the outstanding state in India. According to Guha, Kerala also is at or near the top in suicide rate, drunkenness, and drug addiction. And Kerala is no exception; prosperous countries also tend to be near the top in these habits. Denmark turned Greenland, once a pristine, undeveloped island, into a model welfare state; and Greenland came to have the highest suicide rate in the world. As Guha puts it, "Most of the GDP of an advanced society is a compulsion, not a net addition to welfare. Perhaps another compulsion is an increase in isolation, alienation and suicide." If all economists' calculations are rubbish, what is the best index of people's welfare? Guha opts for "voting with their feet"; if people queue up to migrate from country A to country B, Bwallahs must be better off than Awallahs.

One of the most riveting political shows of our time is the contest between Donald Trump and Hillary Clinton. Who will win? Guha does not take up the question, since his book will sell far beyond the US presidential election, and he would not take the risk of being wrong. But he outlines Hotelling's problem, which is relevant. If a village consists of one long street, and two competing shopkeepers set themselves up in it, where will they locate their shops? They will set themselves up right in the middle of the street, opposite each other; any other location will give one shopkeeper advantage over the other. By the same logic, candidates, whether Democratic or Republican, will be induced to locate themselves near the ideological middle if they want to win. If they just want to make an ideological point, and do not care much about winning or losing, they will take any extreme or absurd position, as Donald Trump has done. And they are most likely to lose, as did Barry Goldwater in 1964. It is such unexpected turns that economics takes that makes Guha's book fascinating. I have given only a handful of his tricks; there are many more in this brief and highly readable book. He also gives problems from time to time for readers to try their economic skills on. There should have been more; if there had been enough, answers to them could have made up Guha's next book. But one never knows; maybe he has something utterly different up his sleeve for next time. Meanwhile, the new model of teaching that Guha has tried out works quite well; despite internet, despite mass tuition shops, good man-to-man-and-woman teaching will not fade out as long as there are a few Ashoks about. Long live Ashoka, the Economist.