There’s been plenty of talk lately –in these pages and elsewhere– about a new kind of capitalism. About creating things because they’re good for society. About understanding, as Michael Porter and Mark Kramer suggest (“Creating Shared Value,” HBR January-February 2011), that not all profits are created equal: Profits derived from making the world better are superior to those derived from the consumption of useless, or even harmful, junk.

At the risk of touching the third rail, I propose that getting people to want things they don’t really need may be far more valuable to society than we think.

Imagine that I started a business selling beautiful bottles of air for $10. I’d call them Respirer (res-pir-AY– it’s French!). My advertisements would laud Respirer’s purity, evoking bracing mountain air. (Fewer than 10 parts per trillion of particulate in every bottle!) Celebrities would endorse Respirer’s rejuvenating effects. (Kate Winslet starts every day with Respirer!) In a matter of months, department stores would be selling out, and spas would brag that their saunas piped in pure Respirer air.

Respirer would be a runaway hit. Of course, it would be just air, and in most places you could get all the reasonably high-quality air you wanted free. So how could this clearly useless product have a beneficial effect on the economy? It would motivate people. By hyping Respirer, I’d give consumers something to want, and in order to be able to afford it, they’d have to work. They’d have to be productive.

We often talk about how marketing’s job is to get us to want things and spend our money, sometimes foolishly. But that reflects only marketing’s output. Marketing also creates input: It spurs us to work to earn the money to buy the things we want.

Consider for a moment a world without marketing hype. One in which there’s nothing you really desire beyond what you need to live. There’s nothing your kids want; they don’t bug you every time you’re in the supermarket. How hard would you work in such a world? What would motivate you to work harder?

Now consider our current consumer environment: Multiply the desire for Respirer by thousands of products of varying levels of utility: iPads, leather couches, crystal martini glasses, cars, garden gnomes. It’s like having thousands of little motivational speakers hovering around us.

Suppose I’m a surgeon. Could it be that my desire for Respirer, and all this other stuff, would spur me to work harder? To innovate new procedures that would save lives and also enrich me personally? I suspect it’s very likely.

Let’s be clear. I don’t mean to say that marketing will save our economy. Or that marketing things we don’t need is the key to a prosperous planet. The line is narrow, indeed, between being motivated to work and mortgaging the future (both your own and society’s) to get stuff like bottled air.

Still, as we continue to redefine capitalism, let’s not discount the role of aspiration and the desire for incremental luxuries–things we want but don’t necessarily need. They can fuel productivity and thus have a valuable function in our economy.

Originally published in Harvard Business Review, May 2011.