If the theory of evolution has taught us anything, it is that most species become extinct, and that there is no guarantee that this will not be as true of the human species as it has been of the overwhelming majority of other ones—from the dinosaurs to our closest cousins in the genus Homo, to Neanderthals and others. That is one reason it is important to ask: what are the main sources of risk in the contemporary world to our continued survival?
We believe that the largest and most immediate risk today is the human propensity to engage in acts of violence, such as the wars and genocides by means of which we now have the power to destroy all human life, if not all life, on earth— particularly given that several of the nations currently in possession of thermonuclear and other weapons of mass destruction are led by...
