This one sounds a little tricky...
List 20 books that changed you. This will clearly get long, so...
They are in semi-random order. Initially by age of exposure, but then by the order I could think them up. Which means some that influenced me more are later than some that influenced me less. But you'll note some common themes.
I'm too lazy to look up authors for ones I don't have memorized, sorry.
The Little Princess - for the way she didn't relate well to people, was disliked by most of the people she had to deal with, wasn't cute, was perceptive, and struggled on through horrible suffering
The Silver Crown by O'Brien - for having a world turned almost totally against the main character. For being dark and twisted and dystopic in a children's book, complete with twisted poetry.
The God's Themselves - "Against Stupidity" "The Gods Themselves" "Contend in Vain" by Asimov - it's three stories that combine to form a single story, even though each part is very different. I like that structure and I think it influenced my writing. But beyond that, the last story has a fascinating lesson about problem solving that I cannot explain without spoilering the stories. The middle part was always my favorite though. Again, an outcast main character that is disliked by most of the people around her. This may be a bit of a theme.
5000 B.C. and also This Book Needs No Title by Smullyan - Raymond Smullyan seriously affected the ways in which I think. It was my introduction to many questions of philosophy and my introduction to some of the answers. I only tend to realize just how much I was affected when I reread the books and agree so very much. This is probably part of why most people don't get the way that I think. I was influenced by an unusual source. Some of the stories in these books are great though. Also, Smullyan is how I learned that I had a knack for knights and knave puzzles. It was something I could just see through and solve. It was the only academic thing that I was better at than my father when I was growing up. It was pretty much the only thing I was truly good at. I know this seems weird to many of you, but in first grade I was the only child in my class who couldn't read and I also absolutely could not do arithmatic. It took me years to be able to do arithmatic (spellcheck says that is wrong, but I'm lazy). I wasn't really good at school for a while. I come from a family of very bright people and I was pretty much bad at everything for a while. And I was the youngest, so everyone was better at everything than I was. Knights and knave puzzles were the first thing were that wasn't the case.
The Hitchhiker's Guide to the Galaxy constellation of works by Adams - they were fun, but mainly, they helped me feel like I fit in with friends I met who would affect my life
Ender's Game by Card - "They have a word for people like us, they call us children and they treat us like mice." For its view of childhood and for its view of sibling relationships. Both were far more true to my experiences than almost any other book. When I finished Ender's Game I immediately reread it.
Godel, Escher, Back the Eternal Golden Braid by Hofstadter - it helped shape my view of why I dislike ants, but I might be friends with an anthill. It helped shape my view of consciousness and personality. And it introduced me to some art.
The Dark Island - for having a protagonist who is utterly cold, utterly focused, utterly helpful, and utterly miserable. For having a character who is barely what most people would think of as human and that I could identify so strongly with. "Problems should be solved by those who see them." And I have tried to live by that.
Alexandria by Gladys Schmidt - for having the faults of both wanting to much, which is common to the human race and therefore acceptable and offering too much which being uncommon is completely unforgivable.
The Gentle Art of Verbal Self Defense by Elgin - for teaching me a bit about verbal self-defense
That's Not What I Meant by Tannen - for giving me more of an understanding and acceptance of differences of dialect and culture. A better understanding that what feels obviously morally superior to me is more a matter of preference and culture.
Aha! Insight and Aha! Gotcha by Gardner - for being full of logic puzzles and statistics in an easy to understand way
Annotated Alice by Gardner and Dodgeson - for being full of Alicey goodness plus explanations and fascinating insights
The Husband I Bought by Rand (a short story actually) - for having a character give up something she wants incredibly much for the only thing she wants more than that, which is to give up her husband that she loves and wants to be with in order for him to be happy, even if she will not be. But she couldn't be either way, since she wanted him to be happy with her and that wasn't an option. This is a story about deciding what you most want and paying for it. I am fond of those because they apply to life. Although she deceives him "for his own good" which in retrospect may be somewhat of a horrible thing to do. But it is certainly the sort of thing I would have done, so it probably influenced me. I am very into giving people what they want at incredible prices.
The Selfish Gene by Dawkins - for giving me a good grounding in what survival of the fittest really means and introducing me to the word "meme" before the meme had spread everywhere.
Bible Stories - this is not actually the Bible but a book of Bible stories I had written for children. The first time I ever recall getting a paper cut was when reading this book. That always felt rather symbolic.
The Language of Flowers - which gave me an interest in the language of flowers
Names for the Baby - which gave me an interest in the meanings of names
The Book of Night with Moon by Duane - this was the first book I read in the series, although it isn't usually where most people start. It gave me words to a concept of supporting life and fighting entropy at high costs. Again a book of deciding what you most want and paying for it. The characters in this series have incredible power, and it neither totally sucks nor is great fun. It costs them, because they use it responsibly. I named the Support Guide So You Want to be a Support Volunteer after this series.
Society of the Mind by Minsky - this was one of the first things I read that was truly cognitive science. I adored it. It told me that I wanted to study this field. It told me that there was a name for the things I was interested in. That the wide-ranging group of topics actually had a field and there were people who knew things about it and they wrote books and I could read them. I haven't read this since high school, but eventually I plan to rebuy a copy.