Could it be a simple as a mathematical formula that expresses only optimism?  This article from Wired Magazine explains rise and fall of the CDO and CDS markets, and the ensuing pain for all Western economies, possibly better than I have read before.

We’ve all heard that Credit Default Swaps (CDS) were at the root of the problem.  But when the one offering the explanation begins to define CDS and the WHY of the problem, our eyes glaze over and we begin drifting off, wondering who will be voted off American Idol this week.

This is a bit technical, but this article by Felix Salmon is well thought-out to be a good, palitable explanation.