In Bruce Nussbaum's recent post, Did Innovation Trigger this Financial Meltdown...?, he makes some fundamental mistakes in framing the question.

For starters, what exactly was the innovation involved? Most of the fancy new mortgage ideas that contributed to the sub-prime crisis have been around for some time (See CDOs). They have just never been used as carelessly or as broadly as we saw in the last five years. Either way, they probably don't qualify as innovations in 2008 -- but it's hard to know because he never defines exactly which parts he thinks are particularly innovative, or if his definition of an innovation includes things that create financial disasters.

But most importantly, he does ask us to examine failures as a tool for learning, and I can rally behind him on that count.

The trap is, like most disasters, a thorough analysis reveals many factors. To learn meaningful lessons demands paying attention to each factor, as no single one can be solely to blame in a crisis this large.

I'm no finance expert, but I've read enough that if you asked me to pick one primary factor, it'd be one from this pile: Greed, ignorance, fools and their money, and downright lack of common sense.

I'm new here at Harvard Business, but I'll bet whatever reputation I have on the following:

The best summation of the entire situation and how we got here is not from where you'd expect. It's not the Economist or CNBC or some other major media business news source. Instead it's the amazing storytellers at This American Life. Take 30 minutes to listen to their analysis called The Giant Pool of Money. It will be the most edifying and enlightening half hour you well spend this month.