The Fence by Lenrie Peters is a self-reflection. It is a poem that reflects the worries of the poet or the poem speaker against so many inner forces.
The themes of the poem are:
(1) The inability to justify one's actions of good or bad deeds.
(This theme is the major reason the poem is considered a moral one; "My head goes round and round/ But I have not been drinking/ I feel the bouyant wave; I stagger/ It seems the the world has changed her garment/ but it is I who have not crossed the fence/ So there I lie/ There where the need for good/ and the "doing good" conflict/ there I lie" the quote speaks much of the poet's concerns)
(2) The unphatomability of humans desired ambitions.
(Lenrie Peters shows that no matter how humans strive for achievements, the balance between past and future will remain confusingly immeasurable: "There where the dim past and future mingle/ their nebulous and aspirations/ there I lie")
(3) The act of aging and its effects on human beings
(In line 10 of the poem, human body is said to age relentlessly leaving the mind with shadows of memories and most of the unwanted things human; things like shrinkages, natural weaknesses, gradual blindness, etc. "There where the body ages relentlessly/ and only the feeble mind can wander back/ there I lie in open-/ souled amazement/ There where all the opposites arrive/ to plague the inner senses but do not fuse/ I hold my head; and then contrive/ to stop the constant motion")