From the writings of Ulan-Tan, recovered after his death:

… It is because Light and Darkness are connected that great sacrifice was required of the Traveler: that which was once in balance was no longer, and to equal Darkness with its Light would take more than had ever been given before.

So the Traveler created Ghosts; Ghosts created Guardians. And afterward, the Traveler became quiet. Dead, some thought, or dreaming.

When a Human being commits an act of great cost, we know this as injury, as muscles torn and bones broken. It requires rest; frequently, it requires intervention to heal. As simple as the helping hand of another to lean on, or as complex as deep surgery: the constant theme that it cannot be done alone. Even to rest safely in quiet requires another to take over the matters of life that cannot be put off, which do not pause themselves simply for the fact of being asked kindly.

So: the Traveler strove greatly, and then became still. How do we believe that it is anything but injured?

The Speaker tells us the Traveler is not dead, and I believe this. It is sleeping, resting from its great deed. The sacrifice made for us, to create us.

There is a debt thus owed.

If we understand that Light is connected to itself—that the Light in Guardians is the same Light as that in their Ghosts, which in turn is the same Light as the Traveler's—then the answer is clear: that those possessed of the Traveler's Light, defended and upraised by it, stand in the best and in fact only possible position to pay back that debt. Who else could even hope to do so?

I argue that our duty is to try. Even the act of defending the Traveler so it may heal is some measure of action. But if there is more that can be done, then we who it has defended owe it to the Traveler to do so.

Remember that, in Light or in Darkness.