OEDIPUS: I thought I heard you say that Laius was cut down at a place where three roads meet.

JOCASTA: That was the story. It hasn’t died out yet.

OEDIPUS: Where did this thing happen? Be precise.

JOCASTA: A place called Phocis, where two branching roads, one from Daulia, one from Delphi, come together—a crossroads.

The crossroads is where Oedipus, unaware, determines his fate by killing his own father—unless, of course, that fate has already been determined for him in advance by some greater power. (In this sense and in several others, the overlap between “The Road Not Taken” and Oedipus the King is considerable.) But before Oedipus makes the choice to attack Laius, he’s neither a king nor a patricide, nor even the person he believes himself to be, since he’s spent his life up to that point assuming he was the son of the wrong man. Before he makes the choice, he’s nothing and anything. He is, you might say, pure potential.

This pause—this brief moment between question and answer—is the essence of a crossroads. At the intersection of roads A, B, and C is a space that is simultaneously all roads and none; it’s the deep breath before a journey can be undertaken, or a transition completed. In a series of essays beginning in The Forest of Symbols, in 1967, the anthropologist Victor Turner outlined a concept called “liminality,” which he originally applied to ritual processes in Central Africa but later used much more broadly. Here is how Turner describes the idea in “Variations on a Theme of Liminality”:

Let us refer to the state and process of mid-transition as “liminality” and consider a few of its very odd properties. Those undergoing it—call them “liminaries”—are betwixt-and-between established states of politico-jural structure. They evade ordinary cognitive classification too, for they are neither-this-nor-that, here-nor-there, one-thing-not-the-other. Out of their mundane structural context, they are in a sense “dead” to the world, and liminality has many symbols of death. . . . But the most characteristic midliminal symbolism is that of paradox, or being both this and that.

A crossroads gives us exactly this scenario. The person who stands in such a place, debating his path, is neither on one road nor on the other: He is literally betwixt and between. This is why, in Frost’s poetry, the liminal is not just a space for “symbols of death” or “paradox,” but a space for performance and metaphor, the great engines of his poetry. A person who is playing a role both is and isn’t the role played. A metaphor joins two terms so that they both are and aren’t each other. The crossroads is, as Frost would say, the only spot in which one actually can travel both roads as one traveler.