Sator Square

The Sator Square (or Rotas Square) is a word square containing a five-word Latin palindrome:

In particular, this is a square 2D palindrome, which is when a square text admits four symmetries: identity, two diagonal reflections, and 180 degree rotation. As you can see, the text may be read top-to-bottom, bottom-to-top, left-to-right, or right-to-left; and it may be rotated 180 degrees and still be read in all those ways.

The Sator Square is the earliest dateable 2D palindrome. It was found in the ruins of Pompeii, at Herculaneum, a city buried in the ash of Mount Vesuvius. It consists of a sentence written in Latin: "Sator Arepo Tenet Opera Rotas." Its translation has been the subject of speculation with no clear consensus; see below for details.

Other 2D Palindrome examples may be found carved on stone tablets or pressed into clay before being fired.

One likely translation is "The farmer Arepo has [as] works wheels [a plough]"; that is, the farmer uses his plough as his form of work. Although not a significant sentence, it is grammatical; it can be read up and down, backwards and forwards. C. W. Ceram also reads the square boustrophedon (in alternating directions). But since word order is very free in Latin, the translation is the same. If the Sator Square is read boustrophedon, with a reverse in direction, then the words become SATOR OPERA TENET, with the sequence reversed.

The word arepo is a hapax legomenon, appearing nowhere else in Latin literature. Its similarity with arrepo, from ad repo, 'I creep towards', may be coincidental. Most of those who have studied the Sator Square agree that it is a proper name, either an adaptation of a non-Latin word or most likely a name invented specifically for this sentence. Jerome Carcopino thought that it came from a Celtic, specifically Gaulish, word for plough. David Daube argued that it represented a Hebrew or Aramaic rendition of the Greek Αλφα ω, or "Alpha-Omega" (cf. Revelation 1:8) by early Christians. J. Gwyn Griffiths contended that it came, via Alexandria, from the attested Egyptian name Ḥr-Ḥp, which he took to mean "the face of Apis". An origin in Graeco-Roman Egypt was also advocated by Miroslav Marcovich, who maintains that Arepo is a Latinized abbreviation of Harpocrates, god of the rising sun, in some places called Γεωργός `Aρπον, which Marcovich suggests corresponds to Sator Arepo.

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