Smartness Risk

We have been witnessing recession in the global economy from October 2007. While there were initial fears that the world was fast sinking into the Greater Depression a la the Great Depression of early thirties of the last century, simultaneous 'quantitative easing' (the technical phrase for liquidity splurge) by all important economies including the US and China ensured that at worst we would suffer a Great Recession only.
What caused the economic mayhem? Global economic imbalances (mainly American deficits and Chinese balance of payment surplus), rapid erosion in home equity in America, over-financialisation of the economy, large-scale securitisation, misselling of derivative products and inevitable ups and downs in global economy have all been blamed for the crisis.
Who caused the crisis? Here the answer seems to be less divided. Brilliant engineers who entered the Wall Street via the business schools were smart enough to invent complex derivatives, clever enough to market them, intelligent enough to alchemise BBB investments into AAA but not wise enough to understand the implications for the economy. They were driven by the toxic combination of intellectual hubris and hedonistic greed. These value-destroyers set off smart bombs which exploded and destroyed economies while preserving and multiplying their own private riches.
What is the lesson for us in this calamitous drama? We should not crave for complexity. Simple Finance should remain as it is. It should not be converted into a rocket science which it certainly is not.