As many would agree, the 20th century was marked by some of the bloodiest and most gruesome events ever recorded in recorded history. Why do words like Hiroshima, Rwanda, The Final Solution, A Great Leap Forward, The Great Purge and many others evoke such vivid images of blood, torture and murder in our minds? And despite those horrific images, what is it that drives us humans to commit such crimes against humanity again and again? These are the kinds of questions that Jonathan Glover, a critically acclaimed ethical philosopher, seeks to answer in the book he spent more than a decade writing, Humanity: A Moral History of the 20th Century. Through Humanity Glover seeks to answer these questions in a way that gives a solution to how we can avoid repeating those crimes in the future. Jonathan Glover, born 1941, is a British philosopher known for his studies on ethics. Early in his career he was a fellow and tutor at New College, Oxford, but is currently a professor at King's College London. He, much like Professor RJ Rummel (1932-2014) of the University of Hawaii who revived and redefined the term democide, believes that humanity and morality experienced their worst and most questionable moments during the 20th century. Throughout his book, Glover considers the moral predispositions that lead humanity to commit barbaric acts of genocide like those committed by so many world leaders before this period. Each chapter of Glover's analysis focuses on a historical event that he tears apart and tries to make sense of. While this approach to the book can at times be distracting and confusing, one must understand that a simple ethical and philosophical analysis of those horrific events is not enough... middle of paper... n Humanity Glover offers a somewhat frightening depiction of the 20th century. Yes, the 20th century was undoubtedly extremely bloody, but there are some professionals such as psychologist Steven Pinker, a Harvard professor, who argue exactly the opposite of Glover. Pinker, in his The Better Angles of Our Nature: Why Violence Has Declined, claims that the 20th century was actually the least bloody in history because human nature changed significantly. It presents numbers that aim to prove the fact that tribal warfare was nine times deadlier than genocide and warfare in the 20th century. Despite these counterarguments, however, Jonathan Glover provides a remarkable analysis of humanity, morality, and ethics in the 20th century that may provide humans with a solution as to how we should all act to prevent genocide and other war crimes in the future of our species..