The most important book you haven't read?

Here's an interesting question for all of you book people out there: What is the most important book you have NOT read that influenced your life? The question is posed by Tyler Cowen, who suggests that readers avoid the obvious answer of the Bible or the Koran.

When I thought about it, I decided the answer for me is Atlas Shrugged by Ayn Rand, which I have avoided reading for more than 30 years. (I did read an excerpt once in another Rand book, For the New Intellectual, which is the only Rand book I have read (and that was many years ago.)

I have connected to libertarians in some fashion or other for decades. (Even this blog counts, although rather to my surprise the readers are not dominated as much by libertarians as I would have assumed.) Most people come to the libertarian movement from reading Ayn Rand, particularly her signature novel, as this book title suggests.  So it seems to me that a large number of people have been brought into my life by a long novel that I've never attempted to read.