Mathematical approaches to geomancy usually focus on its binary aspects. This is probably just Maslow’s hammer: our contermpoary lives are based around digital technology, and we see that technology in historical practices. Shoddy scholarship about historical transmission aside, I think this is less than ideal for a couple of reasons. First, historical geomancy was clearly…

A prognostic sphere is, at its simplest, a device which predicts whether a patient will live or die based (a) on the patient’s name and (b) on astrology. This is its original and most widely attested function. The earliest is witnessed in a 4th century Greco-Egyptian papyri, where it appears as the Sphere of Democritus…

The following is a very rough, in-progress translation of the Golden Table of Pythagoras, a medieval prognostic device with an exciting framing structure. Here begins the book and the teaching of the Golden Table. Master Pythagoras, the noble philosopher who traveled the whole world, seeking wisdom and seeing many marvels, came into the land and…

A curious idea which is attested across all continents is that of a “lost Pleiad”, in which one of the stars in the Pleiades cluster– generally called sisters, virgins, maidens, and so one — fades, either from death, abduction, or even shame. Often, they are menaced by men identified with the constellation Orion. The astronomer…

Emilie Savage-Smith is, undoubtedly, a brilliant scholar and a pre-eminent historian of science. Her monograph with Marion B. Smith on the enigmatic “divination tablet” (below) currently housed at the British Museum has been indispensable to me personally in my current research trajectories. Thus her persistent claim that geomantic dice (found in a variety of medieval,…

Ron Eglash, a mathematician-cum-anthropologist at the University of Michigan School of Information, makes an interesting claim: that geomancy, particularly the sort practiced by Ifa and Bamana diviners in Africa, is at the very origin of computer science. Such a claim is intriguing, of course, especially given my own interest in astrology’s relation to computing —…