The title is a statement in sentence form (without the period). It's totally straightforward. The mind, our speaker states, is an enchanting thing. If this were an essay, the title would be the thesis statement and the poem that follows would be all of the evidence to back up the claim. And well, that's kind of how it works. Even though the examples that follow the title get more and more wrapped up and complex, they stay completely on topic. Our speaker never abandons the original statement made in the title.
The other cool thing about the title is how it runs into the first line of the poem. Most of the time a poem's title is followed by a stop sign: take a deep breath and a sip of your coffee, and then plunge in. Here the first line is a continuation of the title -- all in the same breath. And the first line is a slight adjustment too, saying a similar thing in a subtly different way. It's a very engaging way to begin a poem, for sure.
But you could also read the second line as a jerky restart to the poem, as if the speaker goes, The mind is an enchanting thing—no wait. The mind is an enchanted thing. That's right.
Either way, the title creates quite an interesting relationship between itself and the rest of the poem. It sets us up for what's coming, but also keeps us on our toes. Expect surprises, dear Shmoopers.