Lines 1–6
The main ideas of “The Horizons of Rooms” are introduced in the poem’s first line, with a sharp directness that serves to catch readers off guard. The poem uses the familiar, comfortable word “room,” but it quickly makes clear that it means more by this word than the way that it is commonly used. Readers can tell that they need to think in broader terms when the poem tells them that rooms have existed “for such a short time”: “Such” usually limits “a short time” to seconds or minutes, but such an idea conflicts with any possible definition of “rooms.” Rooms have been around for a long time, and calling their existence short draws a comparison to the time before recorded history when humans did not live indoors at all. This idea sets the poem in historical terms of centuries and eons, broadening the idea of “rooms” to the varieties of caves, tents, huts, or anything else that could be called a room throughout the span of time.

The second line hints at the reason why humans never really consider the rooms in which they live. Living in rooms is so thoroughly familiar that it is taken for granted. The only times that people become aware of being confined to indoor living are when they are unable to go outside, such as when it is raining or snowing. The line break from lines 3 to 4 is a run-on line, meaning that it carries the thought over with just the slight pause required by returning to the poem’s left-hand margin but without any punctuation. Here, the run-on line is used to make readers think two different ideas about one phrase. In one sense, “or very late” can be read as the third example of a situation that would make people stay in their rooms, similar to the rain and snow already mentioned. Whereas rain and snow present natural dangers, this phrase introduces the ways society makes it dangerous to leave rooms, implying that there is a time, beyond late night that is “too” late, when criminals lurk. Reading beyond the line break, however, creates the phrase “very late with everyone else in another room.” This line conjures an image of some lonesome person sitting in the darkness, contemplating familiar objects, such as the walls of a room, isolated from the people that they live with. The first sense of “very late” presents a world outside that is dangerous and confining; the second describes a person suffering from a social separation that is personal and psychological.

Lines 5 and 6 return to the main theme, which was merely implied in the first two lines, making those points more directly. The phrase “time beyond measure” clarifies what the poem meant earlier when it said that rooms have existed for “such a short time,” and the phrase “many have forgotten the sky” restates the idea that, regarding rooms, “we can think of nothing else.”

Lines 7–10
The geological sense that the poem has applied to the word “room” is raised again in line 7, which describes the first room as a cave, presumably during the Ice Age. Here, the poem shows a distinction between what it means by the word “room” and shelters that occur in nature. The cave described in line 7 is just a place with stone and ice, but the addition of a fallen tree in line 8 implies that humans added to what was already there, dragging the tree from where it fell to block the mouth of the cave, making the room complete.

In line 9, the poem balances its images drawn from nature with a reminder of the human presence in the room, representing human life with one of its most common bodily functions, the beating of a heart. The close relationship between nature and humans is implied symbolically in line 10, with the heartbeat of a human echoing off the wall of ice, showing that each is as responsible as the other for the sound that enlivens the room. Merwin uses irony here by linking the life-sustaining heartbeat to ice, which is usually associated with coldness, immobility, and death.

Lines 11–16
Continuing with its historical perspective, the poem focuses on the how the shelter of rooms enabled humanity to survive. Line 11 explains that people could give birth safely once they were able to do so inside. In line 12, though, the poem reverses this view of the room providing security and, instead, makes it seem somehow threatening by repeating the word “room.” The unnecessary addition of the phrase “in a room” so soon after the last use of the word indicates how the idea of the room insinuated itself into human consciousness, becoming present in all aspects of life for people millions of years ago. In lines 13 and 14, the poem asserts that humans came to see everything as a room, even the landscape. This is a reversal of the normal understanding of these ideas, because landscapes are generally thought of as being, by definition, open and natural, whereas rooms are closed and indoors.

Merwin explains how the landscape is seen as a room in lines 15 and 16, changing the concept of a room’s enclosure from the physical space that it generally connotes to a segment of time. In human minds, the mountains mentioned in line 15 are squeezed between ideas of rooms, confined between one memory of a room and another because the minds of humans are so filled with thoughts of rooms.

Lines 17–18
In the poem’s most psychologically complex stanza, Merwin combines memory, identity, and metaphysics. In contrast to the previous stanzas, which discussed the development of ideas from their earliest forms, this stanza uses the present tense voice to describe human thought today. More and more people remember childhood as being a room, the poem says. Rather than just restating the idea that people see things in terms of the rooms that they live in, though, the poem adds a twist in line 18. The idea of childhood as a room is one that these people have after they have grown up, and within that idea they have another, the idea of sitting in that room and thinking of a forest. The poem does not imply that these people could ever have gone to the forest, or even that they may have seen the forest from their childhood rooms, but only that the forest existed within their memories of when they were young.

Lines 19–22
These two stanzas continue with the memory begun in the stanza that preceded them. They describe the world from a baby’s perspective, with “the first hands and the first voices” representing the child’s initial contact with other humans, mentioning the ceiling that the baby, lying on his or her back, would see beyond the people who hover over its head. The use of the word “emerge” gives this memory a particularly vague quality, like the forest that the person is said to remember thinking about in line 18: the memories show up from nowhere in particular and can disappear just as suddenly. Lines 20 and 21 describe a grown person, later in life, lying back and staring at the ceiling, much in the same way that the baby did, but in different circumstances. In the same way that the poem travels back to a time when the human race first started to use rooms, these lines travel back to one person’s awareness of ceilings.

Lines 23–24
Lines 23 and 24 serve to remind readers that this person’s experience of the ceiling is the same as the one that the first person in a room, giving birth in a cave millions of years ago, went through.

Lines 25–28
Line 25 serves to remind readers of how infrequent the practice of sleeping outdoors has become. This might seem an obvious and inconsequential fact, but it fits with the historical perspective that the poem has provided up to this point. Though rooms are millions of years old, people still frequently slept outside, at least on special occasions, such as vacations, or during hot weather, until fairly recently. The number of people sleeping outside has dwindled “by now” to a small minority. The second function of line 25 is to remind readers, through the mention of sleep, of the “unconsciousness” motif that was first introduced in line 17 as a hazy memory. Line 26 shows a social conscience by remembering the homeless, who live on the streets and sleep in doorways. Whereas most of this poem views society’s debt to rooms as a mixed blessing at best, this line shows the homeless aspiring to be room dwellers, sleeping next to rooms that they are not allowed to enter.

Lines 27 and 28 describe the spread of civilization, which is represented by rooms and the products that are manufactured indoors, into areas that have not previously been civilized. The uncivilized areas are identified as being remote and hard to access or else inhabited by poor people who do not own any methods of transportation so that they have to transport the manufactured items by foot. This line refers to “the final uplands,” which is echoed later in Merwin’s career in the title of his 1992 book about the ancient farming communities around the Dorgdone River in France, The Lost Upland. The word “uplands” is mostly used in rural societies to describe either land that is at a higher elevation (which would echo the mention of mountains in line 15) or to describe land that is inland, away from oceans, and thus more difficult for colonists to reach with their man-made products.

Lines 29–34
The last three stanzas of the poem can be seen as a summary of the ideas that have been presented before. Lines 29 and 30 repeat the idea of a room being a starting place, which is expressed earlier in the poem with the image of a child being born in a cave during the Ice Age. The “we” in this line might be a contemporary gathering that actually would convene in a “meeting room,” but it also could serve as a statement on civilized society. The fact that, as line 30 puts it, we “go on from room to room,” is a restatement of the earlier idea that any one human is accustomed to having one ceiling after another over her or his head from birth.

Lines 31 and 32 repeat the idea of memory that was raised in line 17, implying that humans have some innate knowledge of what life was millions of years ago, before there were rooms. As it is stated here, the idea makes sense: These lines do not pretend to tell readers what they might remember about the time before rooms but only state the probable fact that a person entering a room might, on some unconscious level, register some curiosity about what existed on that land long before it was cultivated for human use.

The poem’s final two lines raise a tone that is at odds with everything else it says. There is nothing in the previous thirty-two lines that would lead readers to believe that “living in the room” can be construed as “good fortune.” On the contrary, most of the poem indicated that rooms are a curse, if only because they isolate humanity from the real world. If the poem’s last line is to be accepted as being sincere, then the good fortune of living in the room can only be meant in contrast to the worse fate of what life would be without the shelter that human beings need. This sense of “good fortune” is foreshadowed earlier by the assertion in lines 11 and 12 that giving birth in a room allowed for a successful childbirth and, in line 26, by mention of the hopeful who would like so much to be in a room that they will sleep as close to it as they can get, on doorsteps.