I've spent the day trying to finish drafting Chapter 1 of my next book, due out from Princeton University Press in 2010 as long as I meet my deadline. A key question is what does the concept of 'enough' mean to an economist.

In starting to address this, I've been revisiting the happiness literature. The macro approach using country-level survey data has recently been updated and corrected in interesting ways by Angus Deaton and by Betsey Stevenson and Justin Wolfers. The bottom line I take out of their work is that in fact getting richer does make us happier, at least everywhere except the US (Stevenson and Wolfers speculate that this reflects the dramatic increase in inequality in the US, such that average GDP is an inadequate measure of households' incomes. (Matt Ridley wrote about their paper in the latest UK Wired.)

Another of the types of evidence cited by the 'growth isn't making us happier' folks, however, is rising rates of depression and suicide in the rich nations. I wrote this down as a caveat to my own conclusion, and thought I'd better check it. It's a surprisingly hard factoid to verify quickly. I've now set my research assistant the task. Others' insights or sources will be most welcome.

Meanwhile, on with the wordsmithing.