Gates of horn and ivory

The gates of horn and ivory are a literary image used to distinguish true dreams (corresponding to factual occurrences) from false. The phrase originated in the Greek language, in which the word for "horn" is similar to that for "fulfil" and the word for "ivory" is similar to that for "deceive". On the basis of that play on words, true dreams are spoken of as coming through the gates of horn, false dreams as coming through those of ivory.

The earliest appearance of the image is in the Odyssey, book 19, lines 560-569. There Penelope, who has had a dream that seems to signify that her husband Odysseus is about to return, expresses by a play on words her conviction that the dream is false. She says:

Arthur T. Murray, translator of the original Loeb Classical Library edition of the Odyssey, commented:

Homer greatly influenced Greek literature as a whole.Plato refers to the two gates in his dialogue Charmides:

A reference to the Odyssean image also appears in the late (c. AD 400) epic poet Nonnus:

Virgil borrowed the image of the two gates in lines 893-898 of Book 6 of his Aeneid, describing that of horn as the passageway for true shadows and that of ivory as that through which the Manes in the underworld send false dreams up to the living. Through the latter gate Virgil makes his hero Aeneas, accompanied by the Cumaean Sibyl, return from his visit to the underworld, where he has met, among others, his dead father Anchises:

Two gates the silent house of Sleep adorn;
Of polish'd ivory this, that of transparent horn:
True visions thro' transparent horn arise;
Thro' polish'd ivory pass deluding lies.
Of various things discoursing as he pass'd,
Anchises hither bends his steps at last.
Then, thro' the gate of iv'ry, he dismiss'd

Why Virgil has Aeneas return through the ivory gate (whence pass deluding lies) and not through that of horn is uncertain. One theory is that it refers to the time of night at which he returned.Jorge Luis Borges accepted the view that, for Virgil, what we call reality is not in fact such; that Virgil may have considered the Platonic world of the archetypes to be the real world.

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