As for me, I have to pick some of the modern writers.
Robert Pirsig - Zen and the Art of Motorcycle Maintenance was a life-changing book for me. It's what made me a Philosophy major. I still read it every few years. It's my generation's "On the Road" by Jack Kerouac.
Joseph Heller - Catch-22 is one of my all-time favorite books. It cracks me up every time I read it. If you don't mind the language, it's definitely worth reading.
Douglas Adams - The Hitchhiker's Guide to the Galaxy series got me started in humor writing. The BBC has finished the radio series (I know the guy who played Eddie the shipboard computer in this latest installment), which should be airing anytime, if it hasn't already.
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