I believe is that we can forecast the "changing landscape of context," and thus get insight into when we are entering the danger zone of an X-event.

What distinguishes a mathematical model from, say, a poem, a song, a portrait or any other kind of "model," is that the mathematical model is an image or picture of reality painted with logical symbols instead of with words, sounds or watercolors.

The world is awash in more debt than there is money enough in the world to liquidate it.

The process of globalization has now interconnected almost everything ranging from financial markets to transport networks to communication systems in a huge system that no one really understands.

A good analogy is stretching a rubber band. You can stretch and stretch and even feel the tension increase in the muscles in your hands and arms as the gap from one end of the band to the other widens. But at some point you reach the limits of elasticity of the band and it snaps. The same thing happens with human systems.

The global financial system consists of firms in the financial services sector - banks, hedge funds, insurance companies and the like - and various governmental agencies who are charged with regulating these firms.

If you ask which of the scenarios I think is most dangerous, though, I will give a different answer. In that form of the question, I regard a nuclear attack, terrorist-generated or otherwise, as the most threatening combination of likelihood and long-term damage to modern life today.