It's one of those books that constantly leaves you uneasy and unsure whether you understand what you are reading but what an amazing read.
I'm not a technical book person and I definitely threw this book across the room multiple times during this class. Hardest I've ever fought for an A-. It's not poorly written, I just struggle with math-y books.
http://www.barnesandnoble.com/w/introduction-to-algorithms-t...
One of the few books I kept from college and still pull it out once or twice a year when I need to look up something and refresh/relearn. Incredibly dense.
Regardless, the one that I spent a good year reading through multiple times was Farnsworth's Classical English Rhetoric. A brilliant book that challenged my knowledge of rhetoric and enabled me to hone my rhetorical skills. You can read it to learn or read it just for the awesomeness of the passages.
http://www.amazon.com/Farnsworths-Classical-English-Rhetoric...
Critique of Pure Reason for similar reasons in another of my lifetimes. It's another book I'm not smart enough to criticize meaningfully.
Fiction, clearly Cormac McCarthy's The Road. As a parent it's just brutal to find a place to put it. Not necessarily my first recommendation among his novels, either.
It taught me just how much I was reading for my own entertainment, not for real information.
Most programming books are challenging to me as I'm more of a learning by doing guy and the content is usually either too abstract for me or in form of sample projects that dont teach much beyond mere replication.
But there's one exception, my black horse.
I tried to skim the Bible (Old and New Testament), in multiple translations. Including easy ones, dumbed-down ones, ones for deaf readers, etc.
I thought that as literally millions of people have read this stuff for literally hundreds of years, and it permeates every part of western culture, it would be a walk through the park. Much easier than "more difficult" or specialized stuff.
This is not true. I found it absolutely horrific to try to read it from beginning to end. It's very difficult and basically I gave up, even in situations where I had no other reading material and absoluetly nothing else to do except drink some coffee and try to read it. I found the old and new testaments are unreadable.
This is not just because of the subject matter. For example (I've said this elsewwhere) I found the Qu'ran an incredibly easy skim. You can do it in an hour. (easily, and for meaning.)
Just try it:
http://www.nooresunnat.com/Audio/Complete%20Quran/Quran%20Tr...
This is just 566 pages triple-spaced with mostly blank lines, it's like 180 actual pages. It's incredibly repetitive. You can really stop on the parts that say something.
The whole thing doesn't say much, there's not all this useless geneology and history and names and such. It's easy.
Start skimming now and you'll be done by the time you get an answer to a quick email you just sent. 20-40 minutes if you're fast.
So it's not me. It's not hte subject matter. It's just that the old and new testaments are not the same at all. they're incredibly dense books that somehow made it into our culture while being totally unreadable sequentially. (for understanding.)
obviously it's fine to look up specific verses in. but as a book? Forget it. Even if you're stuck on an island with nothing else, it makes for the most impossible reading you'll ever find in a language you speak.
Probably the most challenging/rewarding book I've ever read was Fuller's Synergetics. It offers an understanding of science and nature that is holistic in a way that is timeless and self-evident.
http://www.amazon.com/Synergetics-Explorations-Geometry-Buck...
Martin Meredith's masterfully researched and written The Fate of Africa completely altered my worldview, and brought into sharp focus contemporary African politics. More broadly speaking, it brought clarity to global politics in general, and our human condition.
I think the book is great fun.
My third is Gödel's Proof by Nagel & Newman.
That shit was tough.
Sometimes is a bit hard to conceptualize the infinite, you know!
I didn't get most of the Zen kōan from this book. But I feel its a great book about the history of Zen.
At a guess, I'd imagine many people would find the complete book challenging because of the unexpected material and viewpoints that can be found in sections of the Old Testament, like: https://www.biblegateway.com/passage/?search=Judges+19:22-30
It has many surprises (like the example you gave). Heck, if the Old Testament was made into a movie, it'd be R rated.
My current favorite scripture is the origin of the pet. It's in Genesis 2:18-19. Adam was lonely in the Garden of Eden, so God provided Adam with animals for companionship. Adam gave a name to every one of his animal friends.
It's an endlessly fascinating book. I have many versions of it for study, but I prefer the King James.
http://www.amazon.com/How-Read-Bible-Guide-Scripture/dp/0743...
It's literally the only book I've ever found unreadable (sequentially.) I tried really, really hard for weeks, and not just once. Multiple times over the course of different years.
man, forget it. It's easier to read a kernel dump.