In the excerpt from Sylvia Plath's "The Collected Poems," the speaker reflects on the predictable and unchanging nature of the universe. The lines suggest that natural phenomena, like water flow and the rising and setting of the sun, adhere to fixed rules and rhythms. This evokes a sense of stability and inevitability in the world around us, contrasting the chaos of human existence.
Additionally, the mention of the "little man" in the moon highlights the idea that there is no controlling force or overseer dictating life's events. The repeated phrase, "is that, is that, is that," emphasizes the acceptance of life's reality, suggesting a resigned acknowledgment of the unalterable truths that govern our existence.