We're talking about should we increase taxes? Why not put a tax on carbon emissions. It would raise a lot of money, it would reduce the environmental damages in the future, it would solve so many problems, and it would be a much more constructive thing to do than to think about raising the income tax.

Risk managers and investment bankers and actually, all kinds of investors took on more risk than they expected. So there was a failure of risk management. There was a failure to recognize how much risk there was in some of these securities that people bought.

I don't think the idea of requiring these to be only sold to people who have already own the bonds, in other words, this naked position that the Germans have recently put into their financial regulation and has been discussed here. I don't think that makes any sense.

If you pay attention to where your exposures are, you might tend up buying credit default swaps against a variety of people that you - companies that you deal with.

If a lot of people feel like this company is undervalued and go out and buy the stock, the stock price will go up reflecting the higher value of this company. You might have information because you trade with them or because you've done some research on them.

I think that's something that investment banks have worried about for a long time and are continuing to worry about, but it's not an easy solution when you have lots of people betting the company's money, how do you really allocate those risks? How do you make sure that the people that take the risks are feeling the risks in an appropriate kind of fashion?

If you have information that a company is not as good as its stock market valuation, you don't have a way to sell that stock unless you already own it. And so that information doesn't get incorporated in the company's stock price as fast if you don't allow short selling.