My grandfather has been dead for quite a few years, but he's still teaching me.
He worked well into his 70's, raised four children on one income, in a small brick-veneer home in a good part of town. Sent each of them, in turn, off to college. Never owned more than one car and, even when he did, drove it little (which was a blessing to everyone else on the road). Walked to work. Walked to the local grocery, hardware and drug stores. Took a bus to go downtown. Was prominent in his local church. Did good in his community and the world. And never earned ten thousand dollars in any year of his life. Admittedly, my grandfather stopped working when the Consumer Price Index was around 40. The CPI is now about 218, so $10K then is a bit over $50K now, but still . . .
That $50K number resonates, in part due to a recent column by David Brooks (no screaming liberal, he). Brooks tells of David Platt, the mega-pastor turned Christian radical (at least by US standards -- in much of Latin America he'd be considered a moderate). In his recent book Radical, Taking Back Your Faith from the American Dream, Platt calls on American Christians to live on no more than $50K (before taxes) per year, and to give away any income above that level. Platt bases his call on the teachings of the New Testament; it's a wisdom with which my grandfather would have agreed wholeheartedly.
There's another wisdom that happens to coincide with that one. The global economy we've got right now is generating about $10,400 per capita, worldwide. Multiply that by two parents and 2-4 kids, and you're right back in that $50K ballpark. Which means that everyone in the world could (in theory) live more or less as well as my grandfather and his family. Of course, most don't. I'd have to guess that even in North America, most families don't live as well as my grandfather did. Not even in the USA, where per capita GDP is around $46K. (Multiply that by five family members, and whether or not the top-end Bush-era tax breaks get extended might almost be relevant.)
Anyway, when people contend that a sustainable economy would mean a decrease in the American standard of living, I wonder. Whose standard of living? How much of a decrease? And would my grandfather even have noticed, were he still alive?