Via Steven Shreve:
To prevent a recurrence of financial crises, some call for a return to a simpler time, before derivative securities and the quants who analyze them–a time when investors bought stocks and bonds and little else.

Such complaints miss the point. When a bridge collapses, no one demands the abolition of civil engineering. One first determines if faulty engineering or shoddy construction caused the collapse. If engineering is to blame, the solution is better–not less–engineering. Furthermore, it would be preposterous to replace the bridge with a slower, less efficient ferry rather than to rebuild the bridge and overcome the obstacle.