Any time a poem asserts that "we were very merry" at the start of each stanza, we're inclined to disbelieve it. After all, who stays "merry" for that long? In the case of "Recuerdo," though, the speaker is so caught up in the joy of re-living a special night that we're inclined to believe her. Whether or not the actual experience of every minute of that night was merry is debatable – but every single moment of her memory definitely is.
The merriness that this poem describes is actually a retrospective happiness. The events of the night aren't as interesting as the speaker's memory of them later on.
The sentiments of one night are so potent that the speaker can capture them even after time, suggesting that they were strong emotions to begin with.
The casualness of the "we" to which "Recuerdo" refers betrays an absolute confidence in the closeness of the "you" and "I" who make up the "we." Does that mean that the couple in the poem lives happily ever after? We have no idea. Were they strangers before that night? We don't know that either. For one night, though, they share a definite friendship.
This poem captures the essence of friendship with its description of a brief, happy memory.
By focusing on a brief, happy memory, the poem allows us to experience happiness without questioning the larger picture of the speaker's life with her friend.
There's something surprising and touching in unexpected generosity. That's precisely the sort of compassion we see in "Recuerdo": a chance gesture that turns out to have deep meaning for the person on its receiving end. It turns out that your actions have an impact on the people around you – even the strangers you pass on the street. Sure, it's not as world-changing as becoming a U.N. goodwill ambassador. But we can't all be Angelina Jolie. Sometimes handing out a piece of fruit can do just as much good on a small scale.
This is a perfect example of compassion: a sudden, instant choice to help someone less fortunate than the speaker.
For all its beauty, this poem describes one of the problems with charity: the speaker impulsively gives everything to the first person she sees without stopping to consider more pragmatic solutions.
One of the miraculous things about "Recuerdo" is that it doesn't try to turn the past into a moral lesson or a revelation or a rationale for a search for Greater Meaning. A lovely set of moments remains just that: a cluster of events that turned out to be a really, really lovely time. St. Vincent Millay layers events on top of each other without pausing to reflect upon their significance. What results is a memory with surprising emotional clarity – without all of the baggage that typically accompanies a poet's turn to the past for inspiration.
This poem is a perfect example of Wordsworth's definition of poetry as something that should capture "emotion recollected in tranquility."
In this poem, memory works best when it looks both forwards and backwards.