"Frogs Eat Butterflies. Snakes Eat Frogs. Hogs Eat Snakes. Men Eat Hogs." is a poem from Wallace Stevens's first book of poetry, Harmonium. It was first published in The Dial in 1922 and is therefore in the public domain.
This poem's title is one of those that rankled with Louis Untermeyer, but Stevens insisted on it in preference to the abbreviated "Frogs Eat Butterflies", which he wrote in a 1922 letter, "would have an affected appearance, which I should dislike." If "The Worms at Heaven's Gate" is about death, then "Frogs Eat Butterflies. Snakes Eat Frogs. Hogs Eat Snakes. Men Eat Hogs." is about aging. The poem takes advantage of quirks of imagery, in this case at the expense of the man whose hours suckle themselves on his being, just as rivers nosed at the banks like swine at a trough. Such quirks may be compared to those in "Anecdote of Canna".