"Guns, Germs and Steel: the Fates of Human Societies" by Jared Diamond (Pulitzer Prize for General Nonfiction in 1997) It's a very interesting read about how societies developed dominance based on climate, agriculture, available natural resources, etc. The second half of the book deals with the development and migration of languages. It's very well written and quite easy to read.

Douglas Addams "Dirk Gently holistic detective" Worth it for the electronic monk

The God series by mike hockney changed my life forever. These books are literal gems. They liberate the mind with ideas all in one place that is unknown to the world for the most part. For a person who doesn't resonate with religion or faith of anything in general, these books gave my life meaning when before I was an antinatalist. This is how empowering these books are.

sapiens by harari. should do it

Sense and Goodness Without God, by Richard Carrier. This changed everything. But that may be too much to digest at once, so I always suggest Fast and Slow, by Daniel Kahneman, because it does not even mention religion but makes one think how mistakes are made.

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And

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Are two to put in the list IMO

Ironically, the Bible. I read it several times, and each time I read it, it seemed less and less plausible.

The bible and pursuing questions that it prompted was enough for me. Final break occurred a bit over 60 years ago and I've been a happy atheist since.

Bertrand Russell....I believe that's how you spell his name, was and early but a goodie

The Cutting Room Floor by Dawn Klehr REALLY made me question everything I ever read about the Bible, such as the obvious, "why were all of the other books taken OUT of the Bible." "Were they trying to hide something?"

Farewell to God: My Reasons for Rejecting the Christian Faith by Charles Templeton

High School, senior year, spanish class. Epic Poem written in "old castilian" "El Poema Del Mio Cid", epic poem about Rui Diaz de Vivar. The Cid. Charlton Heston, Sofia Loren 60's version movie, never remade because Disney hold the rights, but nothing like the epic poem in original antique language.

the godfather. was a great book!

Why I Am Not A Christian
Beyond Goid and Evil

The bible did it for me.

Oh, now that's a tough one - there are so many! Two books I've read several times and will read again are Don Quixote and Orlando.