The cognitive functioning of a human brain depends on a delicate orchestration of many factors, especially during the critical stages of embryo development-and it is much more likely that this self-organizing structure, to be enhanced, needs to be carefully balanced, tuned, and cultivated rather than simply flooded with some extraneous potion.

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.

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.

The first ultraintelligent machine is the last invention that man need ever make, provided that the machine is docile enough to tell us how to keep it under control.

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.

For healthy adult people, the really big thing we can foresee are ways of intervening in the ageing process, either by slowing or reversing it.