Will Wilkinson has a great demolition of the New Economics Foundations' Happy Planet Index. The magic formula: "Multiply life expectancy by life satisfaction and divide it by environmental impact." Here's Will:
I worry that much of the happiness work is ideologically loaded, but most of it is at least an honest attempt study human welfare empirically. Too much of it, however, is stuff like the NEF’s index, basically an attempt to persuasively define something like “happiness” so that it comports with a statist, anti-growth agenda. This is sheer politics brazenly posturing as social science. If the Cato Institute published a study that, say, multiplied life satisfaction by the rate of economic growth and then divided it by government spending as a percentage of GDP, and called it “The Happy World Index, ” would editors think twice? I hope they would. In fact, I bet they would.
Yep. But you can make the reductio ad absurdum even more devastating. According to the Happy Planet Index, you can achieve infinite happiness simply by having zero environmental impact. And the simplest way to achieve that, of course, is not to exist at all.
News flash: Unimaginable happiness is just a massive suicide pact away!