The 13th card of a Tarot suit shows us a teacher, and in computing tarot, that teacher is a person who teaches you about the reflexive, universal nature of computing. For the suit of swords, that teacher is **The Mathematician**.

Computers are a blunt imitation of mathematics. A lot of the development of Mathematics has been motivated by engineering and mechanism, but for digital computers, this is the reverse: the mathematics preceded the mechanism. Behind and beyond and before computers, motivating them, there is a truth. We learned about hypothetical computers as objects of pure mathematics, and then tried to build them in reality.

There is a human element that is easy to miss in the paragraph above - the “We” in “We learned” and “we tried”. The 13th card is the queen of that suit, a person, with desires and motives and limits. Why does the mathematician care? Why does she work? To what end?