In the Star Trek: Deep Space Nine episode "Treachery, Faith, and the Great River," one of the characters is attempting to repair a spaceship. This is a critical job since there's a war going on, but the war is making it difficult to get the needed parts. An alien named Nog explains how he could obtain them by navigating the Great Material Continuum. He explains:

It binds the universe together . . . there are millions upon millions of worlds in the universe, each one filled with too much of one thing and not enough of another. And the Great Continuum flows through them all, like a mighty river, from "have" to "want" and back again. And if we navigate the Continuum with skill and grace, our ship will be filled with everything our hearts desire.

Identify which of the major themes of trade this passage about the Great Material Continuum highlights and explain how it works.