“A Passing Glimpse” is a short lyric by the American poet Robert Frost (1874-1963). It is typical of Frost’s poetry in various ways, including in its clear and straightforward language, its focus on the personal reflections of a specific speaker, and its use of a simple event to provoke thoughtful meditation. All these traits are also present, for instance, in the works that are probably Frost’s most famous poems: “Stopping by Woods on a Snowy Evening” and “The Road Not Taken.” It is partly Frost’s ability to use mundane circumstances to stir philosophical reflection that has helped make him one of America’s most popular poets. His poems often reflect, and speak to, the ordinary experiences of ordinary people.

“A Passing Glimpse” opens with the speaker referring to passing glimpses of flowers seen from the rapidly moving car of a train. The flowers symbolize beauty; the passing train can symbolize various concepts, such as machines made by humans versus the living beauty of nature; the loss of personal contact with nature typical of modern existence; and the hurried pace of modern life (a hurry resulting from mechanization). The main focus of the first two lines, then, is on mutability—relentless change. Mutability is a common theme in poetry, but in this poem the sense of change is exacerbated and exaggerated by the emphasis on a gigantic man-made machine—a machine which, by its very nature, contrasts with the delicate, beautiful flowers. The shift from line 1 to line 2 in a sense mimics the experience of the speaker: in the first line the presence of the flowers is immediately established; in the second line, that presence is instantly “gone.” Line 1 emphasizes the present; line 2 abruptly shifts to the past. The first couplet, therefore, doesn’t simply describe mutability; it enacts it. Line 1 reports a complete experience and a complete thought; line 2 then immediately undercuts both.

If the first couplet describes the experience of mutability, the second couplet describes the speaker’s reaction to that experience. He wants, in a sense, to reverse time, to undo an event that has already irrevocably occurred. If the speaker were walking, running, riding a horse, or even driving an automobile, his desire to “go back” (3) might be possible. The fact that he is a passenger on a train, however, symbolizes the impossibility of achieving that desire. Once again, the train symbolizes the ways in which modern life tends to divorce us from nature and also the ways in which it can often frustrate our own desires and hopes.

In the next two couplets, the speaker mentions a wide variety of flowers, which (he is sure) are not the ones he just saw. Paradoxically, because he cannot name the flowers he did see, he mentions many that he did not see, thus allowing both him and the reader to “see” them imaginatively. This is especially the case because he doesn’t simply list the names of flowers but rather imagines different kinds of flowers in different kinds of natural settings. Thus the poem brings the reader into imaginative contact with the beauty of nature. The poem, in this respect, is the opposite of the train: rather than distancing us from natural beauty by speeding past such beauty, the poem allows us to stop and linger over images of natural loveliness—images created by the speaker, and thus images that exist, thanks to the poem, both in his imagination and in ours.

The last two couplets first raise a question; they then answer that question in a final reflection. The question leads us to think about the nature of our lives and experiences: how much...