In a famous passage of The General Theory, John Maynard Keynes, the most influential economist of the 20th century, likens the profession of stock trading and speculation to a newspaper competition that has readers pick the six prettiest faces out of 100 pictures. The person whose choice "most nearly corresponds with the average preferences of the competitors as a whole" wins the prize. The trick is: Contestants who want to win aren't meant to pick their favorite faces but those they think others are most likely to select as well. It is an attempt to establish an average taste for beauty. If you see a face with a wart on its nose, even if you find warts incredibly sexy, you do not select that picture because you know the average person will probably find warts unattractive. This is the game investors play on the market, claims Keynes.

"It is not a case of choosing those which, to the best of one's judgment, are really the prettiest," he wrote, "nor even those which average opinion genuinely thinks the prettiest. We have reached the third degree where we devote our intelligences to anticipating what average opinion expects the average opinion to be. And there are some, I believe, who practise the fourth, fifth and higher degrees."

I bring this up because of something that occurred to me one night when I could not sleep because of the heat dome that had parked over our region and showed no sign of moving. I was in bed sweating and thinking about a new French film, Gemma Bovery, which I had just seen and is about Gemma Bovery (Gemma Arterton), a youngish and rather ordinary English woman who, after settling in rural France with her middle-aged and average-looking English husband, Charles (Jason Flemyng), becomes the obsession of an elderly French baker named Martin (Fabrice Luchini). The baker is also a failed artist and amateur intellectual, and so can't help but notice the propinquity of the names and circumstances of these Brits and Gustave Flaubert's famous fictional character Emma Bovary.

The baker falls in love with Gemma, who in turn falls in love with a dashing and young local aristocrat. Gemma has had another lover in the near past—a hard-hearted professor. All the men want her, and that is pretty much the whole movie. Thanks largely to Fabrice Luchini's comic performance, it's reasonably entertaining, particularly if you're the kind of person who likes Flaubert references in your romantic comedies.

Now, as I thought about this film (a noisy fan keeping me awake as much as the thick heat), an interesting idea entered my mind in much the same way a breeze occasionally entered through the window, stirring the white curtains. If there were a contest that required me to guess the face that would most likely be chosen as the average standard of beauty by millions of Brits—each of whom would also be trying to guess which face their fellow Brits might pick—I would place my bet on the face belonging to Gemma Arterton, a British actress who in fact did beat an astounding 1,500 candidates for the role of Bond girl Strawberry Fields in the 2008 film Quantum of Solace. Arterton's face does almost nothing for me personally; I'm only interested in it because it possesses features (eyes, nose, nostrils, lips, chin, hair) that I think the minds of others are thinking that this is what others think of when they think of mass appeal.

I can easily imagine other people imagining that Arterton's plainly elegant nostrils possess the sort of elegant plainness that others would imagine others imagining. Her brown eyes have a liveliness that is simple. They have none of the insane intensity of, say, Eva Green—whose eyes could burn a hole through a wall. Arterton's lips are neither small nor full. They have just enough shape to them. I would never pick Cate Blanchett in a contest for average preferences. Her lips have too much shape, and I can imagine someone else not picking her lips because they know everyone else will think that everyone else is not picking them for their excessive shapeliness. There is also the matter of Arterton's cheeks, which are not too rosy, too smooth, or too fleshy, which makes them perfect for a contest of who people think others think is the prettiest on average.

I finally went to sleep around the time the sun rose to roast our city.