An Eidolon is a ghoul or a phantom first written about in Greek Mythology. The word literally means “image of the ideal.”The Eidolons were ghostly women created by Zeus from light and mist. From eidolon.org.
Not very satisfactory as an explanation, but perhaps the only information available. The term came up in the context of Helen of Troy whom, Herodotus wrote, actually was sequestered in Egypt and it was her eidolon that went to Troy. So, Paris had the hot itchies for the equivalent of a Doppelganger??? Hmmm.....
From The Times Online
A Don's Life
January 15, 2011
The face of Paris -- and Cleopatra
|The "Paris" grafiti, Temple at Luxor.|
We were looking for this in the temple (though -- fair dues -- it was the son who actually found it). One idea, according to some article I read, is that this is a Greco-Roman graffiti, which represents the famous lost statue of Paris by Euphranor. But, more than that, so the same article claims, it is also a reflection of the idea, made famous in Euripides' play Helen, that Helen of Troy did not actually go to Troy at all, but only an image of her (an eidolon).
How come? Well, this graffito has been scratched right next to a statue of Nefartari. So here, the argument goes, the Roman scratcher has seen an image which he has interpreted as the eidolon of Helen and depicted Paris next to it.
It was the husband who pointed out that this doesn't quite add up. But something quite close to it does For starters, on the Euripidean version it was Helen who went to Egypt and the eidolon that went to Troy -- so logically this statue of Nefertari can't have been re-interpreted as the eidolon (it's the wrong place). The husband must be right to say that the graffiti artist saw the Egyptian statue (naked) as an image of Aphrodite.. which is why, as in the judgement of Paris, the graffiti figure is holding an apple in his hand, all ready to award it to the Goddess of Love. Still, it is a nice Roman re-interpretation of an Egyptian image, but probably no connection with Euripides.