"Homo Deus: A Brief History of Tomorrow" by Yuval Noah Harari is a good companion to Harari's "Sapiens" in that takes some of the seeds sown in that book and allows them to grow up into a tangled jungle. In fact, feels like a continuation or variation on a theme from the first book. You do not need to read "Sapiens" but it is interesting to see an author take larger idea and repackage them for different arguments. And this is not a pretty package. "Homo Deus" is the kind of book that can keep you up at night with existential dread. Once you read it, you cannot unlearn it and you begin to see Harari's analysis everywhere.

Like its predecessor, this is a macro-history that weaves together big ideas over thousands of years. But "Homo Deus" is more focused on a singular premise. His basic argument is that the three big ideas that will define the 21st Century are 1) a world without suffering, 2) a world without death, and 3) a world where human have modified their bodies through technology. He proceeds to unpack these ideas to show how we have gotten to this point. Many of his larger themes are present here - the idea of inter-subjective realities, the importance of history, how things change, etc.... By the end of the book, the author concludes that the liberal world order we've inherited is also fading, just at the time that advances in technology, biology, and psychology are bringing us to a tipping point when differences between humans could become permanent realities.This book does not end happily and for many, the two possible futures that Harari presents (a techno-utopia and the data religion) are equally scary. But the point is not to keep us scared but to help us see that if we understand where something comes from, we might be able to channel our futures towards a better outcome.

My main critique of the book remains the same as my critique of Sapiens. Harari presents a far too simplistic reading of religion as a language to speak to the changes around us. I am not convinced that religion is obsolete and I think that religion can a means to understand and resist the changes that Harari so starkly describes. I would add that some might find the ideas repetitive if they have read "Sapiens" first but truthfully speaking, the ideas and concepts that Harari describes are important and worth repeating.