quod erat demonstrandum

Having devoted a rather joyful semester of study to Oliver Byrne’s masterful and lucid textbook adaptation of Euclid’s Elements during college, I am finding myself genuinely delighted and nostalgic to see that there’s going to be a re-issue of the authoritative 1847 tome on geometry, illustrating his proofs with colours rather than letters.
The geometer himself provided no pictures and relied on his pupils’ imagination—causing poet Edna St. Vincent Millay to extol that “Euclid alone has looked on Beauty bare” and I even semi-seriously contemplated getting a tattoo of the Pythagorean theorem or another of Byrne’s elegant diagrams—across my back where if I flexed and brought my shoulder blades together (or some such nonsense) the axiom would reveal itself—QED. More to explore at the link above, including a nice primer on the subject.