White Teeth, Zadie Smith Fierce Invalids Home from Hot Climates, Tom Robbins Homage to Catalonia, George Orwell Catch 22, Joseph Heller Timequake; Mother Night, Kurt Vonnegut Jr. Seven Pillars of Wisdom, TE Lawrence The Histories, Tacitus The Catcher in the Rye, JD Salinger (caveat, it was most effective when I read it at 16) Redwall, Brian Jaques (got me really excited about reading when I was in the fourth grade) This list could be much, much longer, but those are the most prominent 'life-changers' that come to mind.
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