After reading a wide variety of books, newspapers, and magazines over three decades, through my more recent addiction to internet news aggregation sites, and in my professional life as an engineer focused on water resources and urban infrastructure planning, I have noticed that predictions about the future tend to follow one of three major tracks. The first track assumes that the future will be pretty much like the past. Our civilization will continue to urbanize and industrialize, we will continue to make slow but steady improvements in technology, in health, and in our overall quality of life. This will happen at significant expense to the natural world, which is regrettable, but we will manage to produce adequate food, produce the energy and other resources we need, and find ways to dispose of our wastes without damaging any critical natural processes that our civilization can't do without.The second track predicts the imminent collapse of civilization. We will run out of fossil fuels and find no viable alternatives to them. Our food production system will collapse. Abrupt and catastrophic changes in the atmosphere and oceans will destroy the ecosystem services our civilization has come to take for granted but will be unable to exist without.A third track envisions a near-term acceleration of technological knowledge so fantastic that it will change our civilization, our bodies, and our minds forever. With the advent of advanced artificial intelligence, robotics, nanotechnology, and biotechnology, today's concerns over energy, natural resources, and pollution will seem silly within just a few decades. On the other hand, these new technologies could give rise to dangers that make 20th-century nuclear, chemical, and biological weapons seem tame by comparison.Are these three visions possibly talking about the same planet? People can have radically different visions of the future because no individual person is able to have a complete understanding of what the world is really like. The world is simply too complex for that. What we do all carry around inside ourselves is a mental model of what the world is like. Some of our mental models are simple, while some capture more of the complexity that is actually out there, but not too much because then our heads would explode. Depending on the mental model a person has and which vision he or she believes is most likely, he or she can make drastically different decisions about what sort of career to follow, whether and how to raise a family, and generally how to conduct his or her life and plan for the future. I once had a high school teacher who said that any idea is only half baked until you write it down. Twenty years later, I see the wisdom in that. Writing forces you to organize your thoughts and then set them down in some coherent, reasonably concise manner. This book is my attempt to write down a wide range of voices and ideas, including a few ideas of my own, and come to some conclusions about what might happen and how I and other reasonable people in our society might want to conduct our lives based on this information.