Defending the Undefendable

What accounts for the fame of Walter Block's Defending the Undefendable? It is a defense of the rights of the least popular professions and occupations in the social order: the advertiser, the miser, the moneylender, the slanderer, the slumlord, the profiteer, the strip miner, the scab, drug pusher, the blackmailer, the addict, the pimp, and so on.
Yes, provocative reading. But there's more going on here. The book is full of theoretical substance. This has something to do with the time in which it was written. Block was in graduate school at Columbia University. His "day job" was to learn things that he had progressively come to believe have nothing to do with economics properly understood.
Meanwhile, the world around him was crying out for economic logic to be brought to bear on a range of human problems. This is when he began to work on this book, essay by essay. It was written on nights and weekends. It was his means of intellectual survival, a tactic for staying interested in real human problems while his mind was otherwise occupied with endless mathematical abstractions.
The book benefits from this timing. You can tell in the sheer rigor of the argument. The subject matter is obviously provocative and popular, but the method of argumentation draws from the highest level of scholarship and logical analytics. The result is that you can learn from this work how to think about microeconomic issues, even as you find yourself drawn to Block's seemingly outrageous claims throughout. The book manages that rare combination of being both rigorous and fun at the same time.
If you are outraged, appalled, offended, and stretched to your limits, your response is exactly what Block intended. That's the idea: to think and consider and imagine liberty as a solution to our social and economic problems. How many books can you name that really achieve that? Not that many. In this sense, this really is a book for the ages.