"The Computation" is a poem about a guy who is bad at math. He thinks that a day contains 24 centuries, not hours. Seriously, this guy seems confused. OK, so you probably already figured out that the speaker is not just confused, but instead up to something metaphorical. Or, rather, "metaphysical."
"The Computation" is vintage John Donne. It's emotional, compact, complex, and almost too clever for its own good. It might not be Donne's most profound poem, but what it lacks in depth it makes up for in wit. The poem is guided by what some poetry people call a "metaphysical conceit." This happens when the poet changes the rules of reality in order to make a subtle point. The speaker of this poem changes the rule that a day has to contain 24 hours, 1,440 minutes, 86,400 seconds.
Despite this straightforward conceit, the subject of the poem remains a mystery to many readers. Is Donne just being cute, like a fourteen-year-old boy who tells some girl that it feels like ages since they saw each other at the mall last weekend? Or has a tragedy occurred, like the death of his lover? Donne and his seventeenth-century peers were experts at sweet-talking women, so we wouldn't put the cuteness option past him, but the poem, particularly in its final lines, also hints at a deep sadness.
Because of its brilliant use of literary devices, "The Computation" is often taught in beginning poetry classes. Its author, John Donne, belonged to the generation in England that came after Shakespeare, which included other "metaphysical poets" like Andrew Marvell and George Herbert. "The Computation" was published in 1635, after Donne's death, in a collection of his work.
Tom Petty was right: the waiting is the hardest part. And when you're waiting for someone you have a huge crush on to get back to you, it's that much worse. Maybe you've had the experience of asking someone out on a date, and they're like, "Ohh…right…I'll look at my calendar and let you know." And you have no idea how to interpret this.
The speaker of this poem and his lover seem to have progressed beyond the first date stage, but now he hasn't heard from her in an entire day, and he's worried. This is the perfect poem for the Facebook/Twitter/texting generation, where 24 hours without some kind of contact with one's significant other often spells real trouble in the relationship. As a result of this interminable wait, the speaker goes combing through his memories, trying to figure out whether she was ever into him, and if so, whether she still has feelings for (or, in seventeenth-century-speak, "favours") him.
Although we hate to laugh at a speaker who seems so earnest and depressed, we can't help but find his account of how time stretches out during a long waiting period hilarious (or at least amusing). And this is a situation with which we can all identify. His experience is like a school kid on the day before summer break, when it seems like the hands of the clock could not move any slower. Five minutes feel like five hours.
Waiting is so much harder when you don't take your mind off the thing you're waiting for. And the speaker never takes his mind off his lover for a moment, even as 2,400 years go by. We're tempted to travel back in time and yell at Donne: "Hey, buddy, a watched pot never boils!" But since he's in love, we'll refrain.