Let others worry about the oil price or China’s current account surplus. On this page, I am celebrating a vintage summer for the economist as personal improvement guru. The “Dear Economist” column, first penned by Alan Beattie and Chris Giles (now FT trade and economics editors, respectively), has celebrated its fourth anniversary. Then Esquire magazine, of all places, was persuaded to publish my full-length feature on what economics could teach its readers about getting a date.

Now Tyler Cowen, an economics professor and prolific blogger at marginalrevolution.com, has published a self-help book called Discover Your Inner Economist.

I have myself long harboured a shameful desire to write a self-help book based on the basic principles of economics, but Cowen got there first. (One of those basic principles is that money doesn’t get left lying in the street for long.) I recommend his book very highly to anyone who enjoys reading this page: it’s relentlessly creative and I loved reading it.

Still, the economics of self-help is a difficult business. This is not for the obvious reason, which is that economics appears to be a narrow subject focused only on money. Economics is far broader than that: two decent definitions of the subject are that it is the study of scarcity (and what could be scarcer than Mr Right?) or that it is the study of rational behaviour.

It’s this second definition that hints at trouble. Economics usually assumes rational behaviour, and so the very idea of a self-help book or a problem page such as “Dear Economist” is subversive to economic orthodoxy. Rational economic agents don’t need self-help books, and they don’t write to problem pages either. If we admit that people need advice, we chip away at the foundations of most economic thought. That is strangely reassuring.

What emerges from any serious attempt to develop an economist’s guide to life is a lesson that every economist should remember: theory is nice, but it needs to be coupled with creativity and, ideally, with some facts.

Cowen’s chapter on appreciating art and music is a case in point. He begins with the economics: scarcity counts, and in the case of art appreciation, what is scarce is time and attention. That’s absolutely right, but we knew it already. Much more interesting are his creative solutions to the scarcity problem. It can be overwhelming to walk through a big art gallery, and so you will appreciate it more if you give yourself a reason to pay attention. Cowen suggests fantasising about stealing one of the pictures, thus putting your well-developed selfish consumerist impulses to good use. Which one would you steal? That’s a question to liven up any gallery visit.

Or if you want to find good ethnic food, Cowen advocates looking for ethnic restaurants in ugly strip malls. The rent is cheap, which means that the places are relatively attractive to new immigrants with new ideas. Starbucks, by contrast, will pay top dollar for a premium location. The theory seems plausible, but its credibility rests on empirical research: Cowen is the author of an ethnic dining guide and has visited an absurdly large number of restaurants.

Economic theory is powerful stuff, but the world is too complex to be understood by a theory alone, and that is true whether designing an aid programme for Ethiopia or trying to find good Ethiopian food.

Taking this lesson to heart, I have dug up a vital piece of empirical dating information: the areas of the UK with the most favourable ratios of young men to young women. But perhaps I’ll save that in case I write my own self-help book. Scarcity matters, after all.

Tim Harford’s book ‘The Undercover Economist’ (Little, Brown) is out in paperback