The book is about evolution, its messiness, glory, sometimes cruelty, and awesome power to create more and more complexity. Darwinian processes, driven by variation, selection, and replication, are fundamental cosmic patterns found not only in biological life but also in the evolution of cultures, technologies, and societies. The only permanent feature of an ever changing universe is the process of change itself. Evolution works by creating complexity and diversity, in an endless search of better adaptation to changing environmental conditions, and ruthlessly discarding experiments to make room for what works. "Natural selection is a process of exuberant creation and ruthless elimination," says Chu. "Similarly, the best practice in science and culture is a kind of negative pragmatism: find out what is not working and get rid of it."

It's not surprising, then, that the most successful product of evolution - ourselves - must necessarily make room for new experiments in the search of optimal adaptation to a wider environment - the whole universe. Chu uses the powerful metaphor of a killer whale - another creature that evolution has placed at the top of its habitat - that jumps out of the water to catch glimpses of other, more challenging alien environments. At this point in human history, "blind" Darwinian evolution is about to give rise to self-directed, conscious evolution. But self-directed evolution will not be a clean, aseptic, top-down, design-review-implementation project.