Book excerpt: Robert Ornstein and Paul Ehrlich explain that we are causing our own problems because we have created a world where our basic mental functions are no longer suitable. We evolved over a period of millions of years to survive in small tribal families on the wild grassy plains of East Africa. Now the way we live has nothing to do with that time and place, but the mental tools that were developed to survive on the savanna have remained unchanged. These instincts were wonderfully adapted to the environment that shaped them. But that world, the world that made us, is gone. Now these same instincts are causing us to destroy the world that we made. The threats we face are of our own making, and we can unmake them. If people learn how we have come to this point, we can restore our hope for the future. NWNM describes the way our minds have evolved, and offers suggestions for how to cope with who we are in the world we live in now. Recent decades have seen remarkable progress in many areas. For example, while not overlooking the abject suffering of millions of people, it is nonetheless true that there has been unprecedented alleviation of poverty and disease for the world's poorest people. There are so many promising and astonishing advances in medicine, technology, and the social and physical sciences that if we give ourselves a chance to survive, our species could enter a golden age.