VIENNA — The most notable innovations of the past two decades have been financial. Like technological innovation, financial innovation is concerned with the perpetual search for greater efficiency — in this case, reducing the cost of transferring funds from savers to investors. Cost reductions that represent a net benefit to society should be regarded favorably.

But as the current crisis demonstrates, where financial innovation is designed to circumvent regulation or taxation, we need to be more circumspect.

Sadly, the financial revolution has been mostly rent-seeking rather than welfare-enhancing in character. It has been based on eliminating, or at least reducing, two key elements of banking costs closely associated with prudential arrangements.