Where It All Goes Down
The setting of the poem, like the theme itself, is very small. The speaker is looking back on a tiny memory, one that he would have forgotten long ago if it hadn't been so bizarre. All the action of the poem happens on top of a tiny flower. The poem makes us—as big human beings—focus on something tiny in order to bring the question back around to us: does some big god look at us and see only tiny little specks?
Of course, the real setting of the poem is wherever the poet is now—days, months or even years after he saw this event take place. We don't know what prompted this memory and these thoughts. It might be an interesting exercise to guess what could have happened to him to begin wondering about this forgotten scene.
At the end of the day, though, we're left with a natural scene that is a bizarre example of design. What sort of madman would throw this kind of setting together? It gets the speaker wondering, and unfortunately this setting provides no comforting answers. Either there is some lunatic up there stitching life together, or else… nobody's up there at all.