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Ancient Greek Computer Reconstructed
afaik_ianal writes "A working reconstruction of an ancient Greek computer, the Antikythera mechanism, which was found at the bottom of the ocean in 1900 has been unveiled and is on display at the Technopolis museum, in Athens. The device is believed to have been used to calculate the positions of various celestial bodies including the sun and the moon on any given date. While some guesswork was required in the reconstruction, the bulk of the design is based on updated X-ray photographs of the device."
"No programming, no modularity, no general problem solving."
Programming was done by selecting and arranging gears. Modularity was accomplished by adding layers, coupling the shafts from one layer to another. I'd even go so far as to say that it's general purpose in the sense of an "Erector Set".
Differential gears make this device far more interesting than any other mechanical clockwork I've ever seen.
My guess is that its an analogue conputer, but there is a good chance that its a clock.
If you are familiar with Ptolemy's "Almagest" you know he models the solar system as a series of epicycles. Until Copernicus' time (and after) European and Arab teaching was that these mechanisms were the physical reality but Ptolomy never actually endorsed that view. What if the "Almagest" was the specs for a dedicated astronomical computer and the Antikythera mechanism is the implimentation?
Then again...clocks became simpler over the centuries. Our modern clocks only show hours, minutes, seconds and perhaps the date. Mediaeval clocks showed years, months, weeks, days and hours as well as planetary positions, seasons, and solar and lunar eclipses. Their mechanisms were more complex than mechanical clocks and watches (remember them?) produced in the 20th century. Mechanical clocks built in the 1970s were more accurate but less complex than mechanical clocks built in the 1270s in Europe. Clocks built in earlier centuries in Arab lands were equally complex. The Antikythera mechanism could have been just one in a line of astronomical clocks.
The linked Economist article says that ancient Greeks (I am Greek) believed in a universe where Earth was at its centre. I don't agree with that. Geocentrism was the most accepted theory, but not all Greeks believed it. There were Heliocentrists in ancient Greece. Search Google for Greek and Heliocentrism and see what you can find. Learn about Aristarchus of Samos.