How can we trace out the links between actions that people take today and really long-term outcomes for humanity - outcomes that stretch out indefinitely into the future? I call this effort macrostrategy - that is, to think about the really big strategic situation for having a positive impact on the long-term future. There's the butterfly effect: A small change in an initial condition could have arbitrarily large consequences.

Are you living in a computer simulation?

Our approach to existential risks cannot be one of trial-and-error. There is no opportunity to learn from errors. The reactive approach - see what happens, limit damages, and learn from experience - is unworkable. Rather, we must take a proactive approach. This requires foresight to anticipate new types of threats and a willingness to take decisive preventive action and to bear the costs (moral and economic) of such actions.

In the next century, we will be inventing radical new technologies - machine intelligence, perhaps nanotech, great advances in synthetic biology and other things we haven't even thought of yet. And those new powers will unlock wonderful opportunities, but they might also bring with them certain risks. And we have no track record of surviving those risks. So if there are big existential risks, I think they are going to come from our own activities and mostly from our own inventiveness and creativity.

Had Mother Nature been a real parent, she would have been in jail for child abuse and murder.

The greatest existential risks over the coming decades or century arise from certain, anticipated technological breakthroughs that we might make in particular, machine super intelligence, nanotechnology and synthetic biology. Each of these has an enormous potential for improving the human condition by helping cure disease, poverty, etc. But one could imagine them being misused, used to create powerful weapon systems, or even some kind of accidental destructive scenario, where we suddenly are in possession of some technology that's far more powerful than we are able to control or use wisely.

Machine intelligence is the last invention that humanity will ever need to make.