The Art of Doing Science and Engineering: Learning to Learn by Richard W. Hamming. This has chapters on a variety of science, engineering, and math topics, and each one has what I found to be pretty good insights and views on them. The Rules for the Dance by Mary Oliver. I already knew I liked certain kinds of poetry, but never really understood why. This book breaks down metrical poetry and explains how it works. The Rules for the Direction of the Mind by Descartes, aka the regulae.
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