The Phaistos Disc: printed, and unreadable

The Phaistos Disc was found in 1908 by the Italian archaeologist Luigi Pernier at the Minoan palace site of Phaistos in southern Crete. It is fired clay, roughly fifteen centimetres across, and carries 241 signs arranged in a spiral on both faces.

It is conventionally dated to the Middle Minoan period, around 1700 BC.

The remarkable thing about it

The signs were not incised by hand. They were stamped, using individual punches — one punch per sign, pressed into wet clay.

There are forty-five distinct signs. That means someone made forty-five reusable stamps and used them to compose a text.

It is, in a limited but real sense, the earliest known example of printing with movable type, by something over three thousand years.

Why it cannot be read

There is one of it.

Decipherment requires a corpus. Linear B was read by Michael Ventris in 1952 because thousands of tablets existed, allowing patterns, repetitions and administrative structures to be identified — and because Ventris could test a proposed value against enormous quantities of text.

The disc has 241 signs total. Even if the language were known and the system were straightforward, that is not enough material to work with. Decipherments of it are published regularly and none can be tested.

The signs themselves are legible and have been catalogued: a plumed head, a shield, a walking figure, a fish, a boat, a flower. What they represent phonetically, or whether they are phonetic at all, is unknown.

How Linear B was actually broken

The contrast makes the disc's problem concrete.

Michael Ventris had thousands of tablets from Knossos and Pylos. Alice Kober had already established, by patient analysis, that certain sign groups varied their endings in regular ways — evidence of an inflected language, and a set of relationships between signs before any sound value was assigned.

Ventris then guessed that certain frequent words were place names, tested the resulting sound values across the whole corpus, and found they generated readable Greek in contexts he had not used to derive them.

The authenticity question

A minority position, argued most prominently by the antiquities scholar Jerome Eisenberg in 2008, holds that the disc is a modern forgery — that its uniqueness, its unusually clean edges and the circumstances of its discovery are suspicious.

The mainstream position is that it is genuine. It was found in a stratified archaeological context alongside a Linear A tablet, and the case for forgery rests largely on the fact that it is unlike anything else.