'Toby Ord has written a powerfully-argued book that alerts us to what is perhaps the most important - and yet also most neglected - problem we will ever face' Peter Singer'The Precipice separates science from hype and will remain the definitive work on existential risk for a long time to come' Max Tegmark, author of Life 3.0Humanity stands at a precipice. We live at a time of unprecedented innovation. Technology is accelerating faster than at any point in history, granting us ever greater power, and creating ever greater risk. In the twentieth century, we developed the means to destroy ourselves - without developing the moral framework to ensure that we won't.The Precipice introduces us to the risks to humanity's future, from the familiar man-made threats of climate change and nuclear war, to the greater risks on the horizon from engineered pandemics and advanced artificial intelligence. With clear and rigorous thinking, Toby Ord calculates the various risk levels, and shows how our own time fits within the larger story of human history. Can we protect the legacy of the hundred billion who have come before us, and secure a future for the trillions of generations that could follow? What can we do, in our present moment, to face the risks head on? Guided by a positive vision of the long-term future, The Precipice is a call for a new ethical perspective: a major reorientation in the way we see the world, our history, and the role we play in it.