Concrete Mathematics features running "graffiti" in its margins—a "comment track" from students of previous editions! Sometimes irreverent, sometimes helpful. Also quotes from mathematicians, and graffiti from TAs…
Book by Graham, Knuth, and Patashnik, via .
Conversation
The geometric proof for the geometric series is brilliant.
The most inspiring examples of scholia are in Diophantos’ Arithmetica margins: here Fermat wrote his Last Theorem, and Chortasmenos around 1400 wrote:
> Thy soul, Diophantos, be with Satan because of the difficulty of your other theorems and particularly of the present theorem.
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I must say, Chortasmenos’ note did help me raise my confidence (or channel my frustration?) while trying to decipher Diophantos’ explanation. Fermat should have bought an edition with bigger margins though.
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