"The Lessons of History" by Will & Ariel Durant 4/5
This relatively short book, one hundred pages, compiles lessons from history. It starts from Earth and its Geology, goes through Biology, then focuses on Human Nature, Race, Characters, Morals, Religion, Economics, Socialism, Government, War, Progress and Decay. I’ve just listed almost all of the chapters. Each including distilled lessons on a given topic.
The Key insight that resonated with me after reading the book is that some aspects of human nature are universal, and we have barely improved through the ages. We tend to perceive our generation as superior to people living in the past, but that is just an illusion and getting to know history helps with realising it.