processing performed by elementary particles moving around, and there’s no law of physics that says one can’t build machines more intelligent in every way than we are, and able to seed cosmic life. This suggests that we’ve seen just the tip of the intelligence iceberg; there’s an amazing potential to unlock the full intelligence latent in nature and use it to help humanity flourish—or flounder. Others, including some of the authors in this volume, dismiss the building of an AGI (Artificial General Intelligence—an entity able to accomplish any cognitive task at least as well as humans) not because they consider it physically impossible but because they deem it too difficult for humans to pull off in less than a century. Among professional AI researchers, both types of dismissal have become minority views because of recent breakthroughs. There is a strong expectation that AGI will be achieved within a century, and the median forecast is only decades away. A recent survey of AI researchers by Vincent Muller and Nick Bostrom concludes: [T]he results reveal a view among experts that AI systems will probably (over 50%) reach overall human ability by 2040-50, and very likely (with 90% probability) by 2075. From reaching human ability, it will move on to superintelligence in 2 years (10%) to 30 years (75%) thereafter. © In the cosmic perspective of gigayears, it makes little difference whether AGI arrives in thirty or three hundred years, so let’s focus on the implications rather than the timing. First, we humans discovered how to replicate some natural processes with machines, making our own heat, light, and mechanical horsepower. Gradually we realized that our bodies were also machines, and the discovery of nerve cells blurred the boundary between body and mind. Finally, we started building machines that could outperform not only our muscles but our minds as well. We’ve now been eclipsed by machines in the performance of many narrow cognitive tasks, ranging from memor