The title of the poem hints that its focus is on a lesson to be learnt in the poem. The poem is about man's cruelty to nature. The persona is lying on his hammock, relaxing and enjoying the tranquility and beauty of nature. Suddenly, the persona's interaction with this paradise is interrupted by small children in stanza two. They chase and are successful in catching a butterfly, disemboweling it before their maid takes them away. In the last stanza, the persona has lost his peace of mind and comments on the inevitability that man will be cruel to nature. The poem is written in free verse. The first stanza describes the relaxation on a Sunday, the second describes what disturbed the persona and the last has the persona reflecting on the lesson learnt. The lesson being that man is cruel to nature, so much so that it can be said it is natural to him.
Stanza 1
The poem opens with a tone of warmth, complacency and comfort but drastically changes to one of annoyance. The religious diction used in the poem, "simple praise .... sings ... hosanna ... sin ...sabbath ...prays" alludes to Sunday being a day of rest and worship for Christians. The lack of punctuation in the first few lines which conveys the fact that initially, the poet was quite relaxed.
Stanza 2
The simile "Frowning like serious lepidopterists" shows how the children take their cruel game seriously. It is doubtful that they are aware of the pain they cause the butterfly. A lepidopterist is a specialist in moths, butterflies etc. The attention the children give to their game is also seen when the poet uses a metaphor to compare their killing of the butterfly to a surgeon, "The little surgeon pierces the thin eyes". In another simile, "Frail as a flower in this blue August air," the poet expresses the view that the little girl is just a fragile as the butterfly, again showing that the childhood game is not malicious but still cruel. There is also the use of onomatopoeias like, "cries" and "screams" to show how disturbing is for the persona to witness what is happening to the defenseless animal. Other animals could easily escape and cry out in pain but the butterfly can only suffer in silence. In addition, a butterfly is harmless and beautiful. The analogy of "the frocks of summer torn" is both important and fitting as it clearly shows that nature's paradise is similar to an entire dress but humans have begun to tear and destroy it. Walcott's pun on "the mantis prays" can suggest that the mantis is resting on its front legs and raised as if in prayer, in keeping with the religious nature of the poem. However, it can also mean "preys" showing how the humans attack elements of nature and destroy them for their own pleasures.
Stanza 3
In the final stanza, Walcott refers to "Heredity of cruelty everywhere." Here he implies that violence is endemic in humans and that even the apparently innocent children have inherited this trait. The final line can be paralleled with the first with the first where the persona is trying to reinforce this cruelty by showing how grass grows up yet, it will only be cut down by the "scythe's design." The scythe is an allusion to the Grim Reaper, a symbol of death who carries a scythe.
