What one fool can do, another can.- Ancient Simian Proverb -

This maxim opens Silvanus P. Thompson's legendary textbook Calculus Made Easy. Richard Feynman used this book to teach himself calculus when he was 15. Many decades later, he was quoted as saying:

“Right. I don't believe in the idea that there are a few peculiar people capable of understanding math, and the rest of the world is normal. Math is a human discovery, and it's no more complicated than humans can understand. I had a calculus book once that said, 'What one fool can do, another can.' What we've been able to work out about nature may look abstract and threatening to someone who hasn't studied it, but it was fools who did it, and in the next generation, all the fools will understand it.”

The notes I write (partly for my own enjoyment and learning process, partly because someone as "foolish" as me might benefit from it) follow this credo religiously.