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Thinking in Numbers

This is a collection of essays by Daniel Tammet, a mathematician and savant discussing things that are only tangentially mathematically related: the way he predicts his mother’s behavior, the things he talks about when he meets other mathematicians, what it’s like to recite pi to 25000+ places. Tammet does a good job bridging the gap between how his mind works and what he thinks other people who are not at that level of mathematical thinking would want to read about and does, to my mind, a very good job.