The True Believer: Thoughts on the Nature of Mass Movements by Eric Hoffer examines what qualities make men to become fanatics and the process by which a mass movement takes hold in a society.
In a book full of interesting insights, perhaps the most interesting (if the most banal) is that based only on their features, there is no difference between a religion, a political movement or a fashion. This holistic perspective give his observations a wryly cynical air, which is strengthened by his horizontal comparisons, across contemporaneous societies; as well as vertical ones, drawing from the history of the west; showing how everything is due to human impulses. And so even though it is a slim book, it is astonishingly well researched as evidenced by its bibliography. That, its cross referencing and aphoristic style make it quite a scholarly work. And it is delightful when one recognizes an unacknowledged reference, such pleasure tempered by the realization that many others have been missed because one hasn't read widely enough.
The book seems descriptive rather than prescriptive. It reminds me of the story told about the state of physics before publication of Newton's Principia. While scientists could describe many natural phenomena, they did not know why those things happened until Newton discovered and published his laws of motion. So this book which seems an expatiation of chapters 10 & 12 of Friedrich von Hayek's The Road to Serfdom is, like Hayek's, limited by dependence on events in Nazi Germany and Soviet Russia to illustrate its observations. Even though this book draws more widely from the history of the world, the rules laid down by its unifying thesis are subject to many exceptions. While these are technically flaws, they don't detract from the quality of his insights. Further, since the subject is human beings, any work that seeks to establish immutable rules predicting their behavior would be extraordinarily ambitious. If such a thing were possible, it would be like the fictional science of psychohistory in Isaac Asimov's Foundation series.
So, this is a good book, easy to read but requiring much concentration to be enjoyed. It is highly recommended. Even if just for bragging rights.