When Kuno is telling Vashti about his journey to the earth’s surface, he describes the desire he felt in that moment to experience the world directly, using a metaphor:
“I felt that humanity existed, and that it existed without clothes […] It was naked, humanity seemed naked, and all these tubes and buttons and machineries neither came into the world with us, nor will they follow us out, nor do they matter supremely while we are here. Had I been strong, I would have torn off every garment I had, and gone out into the outer air unswaddled. But this is not for me, nor perhaps for my generation. I climbed with my respirator and my hygienic clothes and my dietetic tabloids! Better thus than not at all.”
While Kuno’s desire to be naked and feel “the outer air unswaddled” is literal—he wishes he could go outside without his respirator and “hygienic clothes”—his invocation of nudity here is also metaphorical. He suddenly understands that “humanity existed […] without clothes” and that “all these tubes and buttons and machineries” are like heavy garments blocking humans from their true, unencumbered nature. In other words, he realizes that people do not need technology in order to survive—in fact, technology is keeping them from being free. This is one of the many moments in which Kuno demonstrates how he cares more about directly experiencing nature than about the comforts and simulations of nature that technology can provide.
When Kuno is telling his mother Vashti about his (unapproved) trip to the earth’s surface, he goes on a short rant about the harmful nature of the Machine. During this rant, he uses both a metaphor and an allusion, as seen in the following quote:
“The Machine develops—but not on our lives. The Machine proceeds—but not to our goal. We only exist as the blood corpuscles that course through its arteries, and if it could work without us, it would let us die. Oh, I have no remedy—or, at least, only one—to tell men again and again that I have seen the hills of Wessex as Aelfrid saw them when he overthrew the Danes.”
The metaphor here—in which Kuno equates humans with “blood corpuscles” (or blood cells) that “course through [the Machine’s] arteries”—communicates his disdain for the Machine’s power and reach. In his mind, humans have come to exist in service of the Machine rather than the Machine existing in service of humans, as its creators originally intended.
The allusion comes in the final line of the passage when Kuno states that the only “remedy” for this reversal of power is for people to hear his story of reaching the earth’s surface, which he compares to Aelfrid seeing “the hills of Wessex […] when he overthrew the Danes.” Aelfrid (also known as Alfred the Great) was the king of an ancient kingdom in England whose victory against the conquering Danes earned him great praise and a nearly mythological status. This allusion helps readers to understand how Kuno sees the Machine as a violent force attempting to conquer humankind (and nature) and how escaping its reach is the only option for true freedom. If people hear his story, he believes, they will feel inspired to join in his crusade against this harmful technology.
Near the end of the story, as the Machine and the underground city are collapsing around them, Vashti and Kuno grieve for themselves and for humanity as a whole. The narrator captures this moment using an extended metaphor, as seen in the following passage:
Man, the flower of all flesh, the noblest of all creatures visible, man who had once made god in his image, and had mirrored his strength on the constellations, beautiful naked man was dying, strangled in the garments that he had woven […] Truly the garment had seemed heavenly at first, shot with the colours of culture, sewn with the threads of self-denial. And heavenly it had been so long as it was a garment and no more, so long as man could shed it at will and live by the essence that is his soul, and the essence, equally divine, that is his body.
The metaphor here compares the Machine (and technology generally) to clothing. When Forster describes how “the garment had seemed heavenly at first, shot with the colours of culture, sewn with the threads of self-denial,” he is trying to capture humanity's experience of first developing technology. While people were excited about technology’s initial possibilities, Forster is arguing, they were also in “denial” in the sense that they refused to think about the potential negative consequences of such technology (like the ones Vashti and Kuno are experiencing in this moment).
Forster continues the metaphor, implying that technology is only positive if people can “shed it at will” like a piece of clothing and live without it. This is not what the humans in the story have done—they relied fully on the Machine and are now “dying, strangled in the garments that [they] had woven.” This damning statement is one of the moments in the story when Forster seeks to warn his readers in the early 20th century about the potential pitfalls of the technological advancements of his time.