What we define as a bubble is any kind of debt-fueled asset inflation where the cash flow generated by the asset itself - a rental property, office building, condo - does not cover the debt incurred to buy the asset. So you depend on a greater fool, if you will, to come in and buy at a higher price.

Dubai was a property bubble. Plain and simple. Go to Dubai and see what happened. It was... what I call it the 'Edifice complex' - it's just, we can grow by putting up lots and lots of buildings and trying to attract people to come here, stay here, and put up offices here and sooner or later, you put up too many.

There's almost 70 billion in square feet under construction in high rises in commercial, residential and light manufacturing. And we estimate about 30 billion square feet, and that's with a 'B,' is commercial, that we would just consider office space. To put that in perspective, that's a 5x5-foot cubicle for every man, woman and child in China.

Derivatives in and of themselves are not evil. There's nothing evil about how they're traded, how they're accounted for, and how they're financed, like any other financial instrument, if done properly.