The key to sparking a more vibrant, thriving economy is a higher purpose.

The crisis of the noughties is kind of like Jaws: just when you think it's dead, it keeps coming back for more. Unemployment, European stability, interest rates, and the specter of another Great Depression are just a few of the issues that have economists concerned...again.

Yet, a great schism divides them. Each side's answers seem incomplete to the other. On one side, Keynesians. On the other, "austerians." The former argue: spend, spend, spend, for the real problem in the economy's a lack of demand — not enough buying power to create jobs and trade. The latter argue: cut, cut, cut, for the real problem's a lack of supply — a shortage of financial capital, to fuel ever-growing debt.

Yet, though it might be fervent, the debate's anything but new. As this ridiculously nerdsome (yes, that's nerdly plus awesome) rap duel between them explains, in fact, it's been raging since Keynes and Hayek went for each others' jugular in the wake of the Great Depression.

Sounds intractable, right? It just might be — because both sides are arguing over the same thing: how to kickstart growth in gross domestic product. Because, in turn, the assumption from both sides is the same: that "growth" is necessary and sufficient for prosperity. In other words, common to both sides is the dogma that the purpose of the economy should be (maximizing) the volume of gross product.

I'd like to propose a third position in this great debate. Call it "prosperianism." Prosperians believe the economy's central problem isn't a lack of demand, or a lack of supply — but a lack of purpose. Prosperianism's foundation can be summed up in a single sentence: 21st century economies can, should, and must have a higher purpose than product.

Prosperians believe that the real challenge of the 21st century isn't kickstarting "growth" and churning out more "product" — but reconceiving what is growing, how it grows, and why it grows. The prosperian agenda is redefining prosperity, so it's more meaningful, authentic, and durable. It's not about just restarting the same old industrial-age engine of GDP, but building a better one.

More from Umair Haque @ Harvard Business Review