I saw a stricken virgin tear dead Dionysus’s heart from him and take it away, and the muses sang that it was a great year, as if it were a play.
Another Troy must rise and fall, Argo’s bow must sail again, and the stories of the Roman Empire must occur again. Everything that man enjoys will cease—love itself ends its glory, as does the glory of battle.
Yeats was a playwright himself, and helped to found Ireland’s National Theatre in 1904. But he was always bothered by the non-immediacy of language in plays. Events were reenacted, but the audience could not be made to really feel them as they might in real time, or even in poetry.
Yeats begins this poem with the death of Dionysus, the god of revelry. The muses singing as if in a play is an insult to the event: it takes away its immediacy. Only the virgin properly feels the enormity of what has occurred. The speaker continues that the events of the Trojan War (Argo was one of the boats used to attack Troy) must replay over and over. But each time after the fact they are staged, and thus lose something of the original.
In the last stanza, Yeats moves away from Classical imagery, and generalizes about the human condition. Desire withers the very thing it desires, climax is the beginning of the end, and when great events are redone—as in a play—they intrinsically lose some of their luster.