Polarity minus

The composer and musicologist Ernst Levy (1895-1981) touched on architecture in an essay on the proportions of the southern tower of Chartres Cathedral. Unoriginally, he appealed to the proportions of the Golden Mean as the cathedral’s guiding principle. His theories hold greater significance in music however. In his book Theory of Harmony, first published in…More

Negative substitution

Cryptographers substitute one symbol for another following a system, so that the recipient who knows the system (and/or a decryption algorithm) can reverse the substitution process to recover the original symbol sequence, i.e. the plain text message. Substitution is a common operation in mathematics, symbolic logic and computer programming. At various times it’s also informed…More

The sky alphabet

A quick google image search on “things that look the same” reveals not just how similar to each other rocks, fruit, trees, animals, food, buildings and people can appear, but how sharply tuned is our propensity to find similarity wherever we can. The philosophy of the French scholar Jacques Gaffarel (1601-1681) exemplified a pre-modern understanding…More

The secret machine

There are at least three touch points connecting the Baroque mathematician and philosopher Gottfried Leibniz (1646-1716) with secretiveness. 1. A cryptographic machine Leibniz invented and built a mechanical calculator. But less well known is his unbuilt model of a machine for encrypting and decrypting messages, using the poylaphabetical encryption method. In his account of Leibniz’s…More