Is medical computing 2,000 years old?

Scientists from Cardiff University, working with colleagues from the universities of Athens and Thessalonica, have established the exact configuration of the world's oldest computer. The device, more than 2,000 years old, is similar in principal to the difference engines built at Harvard and Manchester in the 1930s to calculate nuclear reactions. The device, known as the Antikythera Mechanism, allowed the accurate calculation of complex differential equations.

Historians and scientists have puzzled for over a century over the mechanism's purpose. However, the functions described by the joint British-Greek team in their report in the journal Nature, as well as its intended destination, suggest that it may well have been used in contemporary Greek medicine. As such, it could have been the world's first medical-computing device.

The mechanism was discovered in 1901 by a Greek sponge diver in the sea between southern Greece and Crete, on a Roman ship that had sunk around 70 BCE. The rest of the cargo appeared to come from the island of Rhodes, on the Ionian coast. This area, which included cities such as Ephesus, Pergamum and Smyrna, was the birthplace of modern science and philosophy. At the time of the Antikythera shipwreck, it had the largest concentration of universities and libraries in the world.

The British-Greek team used CT scanning to establish that the mechanism had 37 gear wheels. The device was able to follow the movements of the moon and the sun through the zodiac, predict eclipses and even recreate the irregular orbit of the moon. It could also determine the exact position of the five known planets at any given time.

A reconstructed Antikythera Mechanism
© The Antikythera Mechanism
Research Project

The scans showed that the mechanism used a differential gear, previously believed to have been invented in the 16th century. The level of miniaturisation and complexity of its parts is comparable to that of 18th century clocks.

Mike Edmunds of Cardiff University said: "This device is just extraordinary, the only thing of its kind. The design is beautiful, the astronomy is exactly right. The way the mechanics are designed just makes your jaw drop."

The question remains: what was its purpose? Its ability to fix the position of all the planets, the sun and moon at any given time, suggest that it could have been intended for use in Greek medicine. Its presumed destination — Rome — makes this even more likely.

The Romans had little taste for liberal Greek sciences, which they tended to dismiss as idle speculation. Greek medicine, however, had enjoyed growing patronage in Rome since the 2nd century BCE, and the Romans accorded it the same esteem as engineering and architecture.

By the time of the Antikythera shipwreck, there were many hundreds of Greek doctors working in Rome. In the period just before the shipwreck, the Greek doctor Ascepliades had transformed the practice of medicine and Roman life. Ascepliades, who died in 91 BCE, replaced the foul-tasting medicines of conventional Greek medicine with hot baths and rest cures: he was the first society doctor. More than anyone, Ascepliades introduced the Romans to luxury and began the craze for bathhouses that characterised their way of life during the empire. As a result, Greek doctors and medicine became even more popular in Rome.

Greek medicine of this period was based on the theories of Hippocrates of Kos, an island close to Rhodes, and his theory of the four humours. Greek doctors believed that the humours were determined by the relative positions of the sun, moon and the known planets in the zodiac. Hippocrates himself said: "He who does not understand astrology is not a doctor but a fool."

This points to the most likely application for the Antikythera mechanism as being the first medical computer, as it allows a complete and accurate Hippocratic diagnosis to be made at any time of the day, in any weather.

The survival of the mechanism is a fluke. Most devices made of bronze and brass, including almost all original Greek sculptures, have been lost because they were melted down and recycled. Only two Greek original sculptures exist, both bronzes from Roman shipwrecks. It is possible that a large number of Antikythera mechanisms existed. The Roman statesman Cicero, who lived at the time of the shipwreck, describes a device exactly like the Antikythera mechanism, and claims that it was invented by Posidonius of Rhodes, the Stoic philosopher. Ironically, Stoic logic was rediscovered in the Renaissance, and formed the basis for the development of modern science.