"The Prince" by Niccolò Machiavelli. It's a poison that is surprisingly relevant.
This is a handbook for rulers on how to run a kingdom. The chapters are well organized, starting with how a person might acquire a kingdom, followed by various means they can maintain and defend their state, and ends with some general best practices. Each chapter starts a general topic and a very clear guidelines, followed by extensive examples from historical rulers. An example topic might be whether a ruler should prefer to be cruel or merciful, and the recommendation would be "it is much safer to be feared than loved [...] for love is held by a chain of obligation which, men being selfish, is broken whenever it serves their purpose; but fear is maintained by a dread of punishment which never fails." This is followed by a story of the cruel Hannibal. It's a great handbook as far as writing style goes.
Style aside, the content of the book is poisonous. Like the example above, the ideas and methods of this book are not exactly nice, more like they are uniformly blunt. You may read this book, agree with everything that was said, and confirm that you are in fact a mean person. Or you might disagree with it at first, but search your feelings, you know it to be true. Machiavelli made some fairly convincing arguments to lure you to the dark side. That, or perhaps you enjoyed the anecdote where Hamilcar called a meeting one day and just killed off all senators and rich people, in which case you are already deep in the dark side.
You might stay away from the dark side, but this book is still surprisingly relevant. You don't necessarily need to be involved in politics at a national level, simply substitute "prince" with "person(s) in management chain" and see how it might apply to office politics. In particular, if you observe some chaos and disorder that doesn't seem to make sense, there just might be a chapter in The Prince that explains how someone is attempting a hostile takeover of your project, your team, or your company. It is quite uncanny if you really read into things. And quite poisonous.
Prior to this book, I had read one other book that was categorized as political science, and I found that one to be fairly dry, so I wasn't interested in reading this one at all. But this book has somehow passed through the hands of my comrades to me through some strange circumstances (which are unrelated to the TSA sticker on the cover), so reluctantly I started reading. In the end, I was really glad I read it. I am not sure if I should enjoy it, but I did.
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