2.3 Numbering
"To this day, the theorem of Pythagoras remains the most important single theorem in the whold of mathematics.  That seems and extraordinary thing to say,m but its because its the first time the structure of nature is translated into numbers.  And the exact fit of the numbers describes the exact laws that bind the universe".
J Bronowski
graphic
Part of Arabic commentery on Pythagoras's theorem, circa 1250