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?

Allowing short selling is allowing people to sell - instead of having to buy the stock and then sell it, which doesn't do much; allow them to sell it, and then buy it. In which case they can express that information and the idea is that you would get more accurate valuation of companies by letting people express both their positive information and their negative information through either long or short selling.

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?

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.

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.

I mean, we've always had gold bugs, but now we sort of realize that Treasure Bills might be in the same category. And we have derivatives like credit default swaps which are in this category, and we have derivatives like volatilities that are actually an asset class that we can invest in which are now - would out perform if we have another financial crisis.

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.