Let's touch lightly upon the poem as aphorism. Most poets don't deliberately write aphorisms and call them poems, probably because aphorisms are innately stodgy: they flaunt rather than hide their didactic role of summing things up, so that you can't read too many of them in a row without cleansing your palate between doses.
Hint: the aphorism too often can sneak into the last stanza as a way of validating and “clarifying” the good intentions of the poem.
However, the (often hidden) aphoristic tendencies of poetry can be fun to mess around with as a kind of literary device. I would even go so far as to say a well-placed aphorism can completely change the “body chemistry” of the entire poem, even if in itself it seems innocent of any such intention.
Here are a few one-liners from Greek poet Yannis Ritsos (died, 1990), ably translated by Paul Merchant in his book Monochords. Ritsos regarded them as daily warm-up exercises.
Ritsos was possibly writing one-liners in the tradition of Heraclitus (c. 500 BC) whose tendency was more majestic (tr. by Brooks Haxton in Fragments: the Collected Wisdom of Heraclitus):
A contemporary poet, and there may be many others, who very deftly uses an aphoristic approach (think: summing everything up in the last line) is Lawrence Raab. Here's the final 1 ½ stanzas of his poem “Lost” (Hampden-Sydney Poetry Review, Fall 2017)
And here's the stunning final line of one of my favorite poems by Jorie Graham, 'Subjectivity' – a long poem that labored mightily and brought forth a yellow butterfly!
To finish, here's a poem of mine in which I deliberately succumb to the tangled logic that can be the death of a good aphorism.