The title is taken from line 17 of the poem. Our speaker really likes to get the most out of his words. Why use different ones, when the same old phrase will work as a title, right? He's like a cheap handy man who can fix your stuff with recycled material, only our speaker is making a poem and he's recycling words.
But we know if he's repeating something, it must be important. "Keeping Things Whole" is a brief explanation of why our speaker "moves." Only he's not moving from one neighborhood to another, and he's not talking about his dance moves. For this speaker, "moving" is how he escapes the constant danger of becoming an "absence." Like, if he doesn't keep moving, he'll die, or get swallowed by the field, or become an absence, or vanish, or something equally creepy.
And let's not forget that our speaker could also be a bit overly courteous, as in, he keeps moving because he doesn't want to mess up his surroundings. If he's the embodiment of absence, then it's like his presence is puncturing a hole in the world. Imagine a puzzle with one vital piece missing. That missing piece would make the puzzle whole and complete. Well, our speaker is that missing puzzle piece, and when he moves, the puzzle goes back to looking complete.
So maybe his reason for moving is so that he doesn't fragment and destroy the world around him. It's another contradiction the speaker inhabits. He says he moves because he doesn't want to vanish, yet he also moves because he wants "to keep things whole." It's unclear if he's more concerned with himself or his surroundings, and that uncertainty is what adds to the speaker's uncertainty about himself.
Sure, there's a lot of anxiety in the speaker, but it's eerily stuffed beneath a calm demeanor. That internal anxiety bound inside a matter-of-fact expression is exactly what the title embodies. It sounds both calm and collected, like someone who makes a list to plan his decisions—someone who keeps his stuff together—but also like a warning, as if the speaker is talking to both himself and the reader, saying, "I must move or else I vanish."
You could also say the title is echoed later in the poem. You know, an echo, like when you're standing in a cave, or a field, or a large open space, and you say something and then, magically, it's as if the open space repeats your own words back to you? Well, the poem does the same thing.
The poem is a type of field for the speaker, and it's as if he's talking to himself and his internal dialogue is mapped out in lines of poetry. So, his thoughts are all about how he is "keeping things whole," and that idea is echoing in his mind just like it's echoed in the poem, poem…poem.