The walkways that crisscross the University of Chicago campus are usually well-groomed, unmarked. But in the days following the 2016 presidential election, they became a riot of chalk: slogans, quotes, and hashtags, scribbled in different colors, sizes, and scripts. One graffito in particular stopped me in my tracks. It read: “Every night ends.”
Taken literally, the statement is beyond banal—but, of course, that's not how it's meant to be taken. Rather, it’s an example of a curious type of metaphor that my ears (and eyes) have perked to in recent months. According to this pattern, an idea about time at one scale is expressed in terms an idea about time at another scale. In the graffito, an idea about a period in history is expressed in terms of the rhythms of night and day. It's the same pattern that motivated Reagan’s memorable ‘It’s morning in America’ ad.
Once you're tuned in, it turns out that “time for time” mappings like these are not at all uncommon. Consider the biblical injunction to eat and drink “for tomorrow we die”; or Kazuo Ishiguro’s resonantly titled Remains of the Day, about a butler’s end-of-career reflections; or the concept of a “May-December romance”; or the idea of “sunsetting,” which now enjoys a stand-alone figurative sense in the dictionary; or, finally, graphics that recast the history of the earth or life in the more familiar framework of a 24-hour day (e.g., this one). This scattershot list could, of course, be expanded.
“Time for time” mappings are fun to catalogue and interpret for the all the reasons metaphors generally are fun to catalogue and interpret: they speak to the restless creativity of the human mind, our untiring drive to enliven dull ideas. But this under-appreciated pattern also exposes a deeper theoretical issue. A refrain among researchers in the field is that metaphors involve talking or thinking about an abstract domain in terms of a more concrete domain. A canonical case of such concrete-for-abstract mappings is the use of space (a concrete domain) for talking and thinking about time (an abstract domain). It makes good sense, the story goes: humans have vivid, visceral experience with space, but only indirect, fuzzy experience with time. So, naturally, when we want to express something about time, we reach for the concrete framework of space.
Compelling as it is, this story only take us so far. To make sense of why people might find comfort in the idea that "Every night ends"—a figurative expression that uses the abstract (time) for expressing the abstract (time)—we need a different account of why metaphors work. But what does that account look like?
1. I’m hardly claiming, of course, that the only interesting thing about these figurative expressions is the mapping between time scales. There is often other stuff at play—most obviously, associations with light and darkness, night and day.
2. The ad is memorable enough that it has its own Wikipedia page. Memorable enough, in fact, that Hillary Clinton, in her acceptance speech at the Democratic National Convention in 2016, riffed on it by saying that Donald Trump had “taken the Republican Party a long way, from ‘Morning in America’ to ‘Midnight in America.’”
3. For a discussion of the flagship case of using space to think about time, see the recent reviews that Rafael Núñez and I have written in Scientific American Mind and in Trends in Cognitive Sciences.