Americans love to obsess about wealth, but we're less mindful of the small act of discretion that makes wealth possible: not spending that dollar we just earned. After all, wealth isn't a measure of the money you've spent and consumed, but rather an assessment of all the lucre you put away in an account or pooled together to buy an asset whose value you hope will grow.

The math of savings isn't hard. But, for Americans, the act itself seems quite impossible, as the U.S. has one of the developed world's lowest savings rates, despite the fact that the richest Americans easily put aside half their salary. The culprit isn't only in our wallets and price tags, but also in our brains.