“Now” actually happened a split second ago: A meditation on the passage of time.
Time flows: steady, unstoppable, invisible. The Greek philosopher Heraclitus imagined time streaming through existence, an inexorable medium of change. We understand it scientifically as a hidden background evident in the synchronized beat of clock hands or more precisely in the attosecond pulsing of beryllium ions. But our ordinary perception of time suggests that it is inconstant, elastic, rhythmic. Time flies; time drags on.
In moments of intense engagement—when conversation flows, when work gets done or when “fun” seems such an inadequate description—time moves in great, condensed chunks. By contrast, at a traffic light or in an anxious waiting room a plodding second hand expands time, marking ever widening, frustrating intervals. Time crawls, spreads out, and rises to thwart our plans.
It’s easy to dismiss these varied perceptions as merely fanciful, or as evidence of humans’ limited time-sense. After all, clocks keep rolling no matter what our feelings tell us. But this inconsistency has long perplexed philosophers and intrigued artists, particularly as modern science has managed to mark time ever more precisely.
We seem to occupy an instantaneous present that moves from the past toward the future, but what constitutes the present we feel, and how does it occupy time? Consider this simple event: A horse gallops by, 30 feet in front of you. You see the horse and hear it. Light bouncing off its head, mane and flanks reaches your eyes in about 0.000000033 seconds; the sound of its hooves reaches your ears in 0.27 seconds. You feel vibrations through your feet a bit later. Each of these impulses travels up shorter or longer neural pathways to your brain, which processes them and puts them in order. All of this seems to happen “now,” but, considered precisely, it is already past. Physics and physiology never allow us to live in the present. Meanwhile, you smell plants and soil. You hear shivering blades of grass in a light breeze; you brush a fly off your forearm into the sunlight. An ambient “now” encompasses the “now” of the running horse.
The early 20th-century phenomenologist Henri Bergson described internal consciousness of time as a kind of personal duration. Everything we witness extends across time. This gives time different rhythms and densities that “measure the degree of tension and relaxation of different kinds of consciousness and thereby fix their respective places in the scale of being.” The experience is so real for each of us, he argued, that we must consider it our primary measure of what happens.
In the context of experienced reality, homogeneous clock time, Bergson said, is “an idol of language, a fiction.” This fiction appears, paradoxically, in the precise pioneering work of photographer Eadweard Muybridge, who settled a persistent question about the horse’s gallop—whether all four hooves ever leave the ground simultaneously. The actual movement is so quick that human perception can’t tell for certain. Muybridge demonstrated with 24 bulky cameras capturing 24 successive instants that, yes, they do for an imperceptible, but recordable, moment. At the time, people found his images both informative and unsettling, because the cadenced frames caught the “truth” of the horse’s awkward, imbalanced positions frozen in the midst of what is so evidently fluid, graceful movement.
Artists often take pleasure in exposing this variability of perceived time. Sculpture and literature seem especially suited to the effort. Myron’s memorable Discus Thrower, sculpted in about 460 B.C., arrests the rotating arc of an Olympian’s body, weight balanced, muscles rippling, and anticipates the release of the projectile. The extended event is not so much stopped, as compressed into bronze. Twenty-four hundred years later, in 1967, the Italian writer Italo Calvino, with similarly classical flair, checked a springing lion, poised hunter and launched arrow in t zero. Its 17 pages ponder the immanence of death or survival but end with the three objects perpetually suspended in an ellipsis. “In literature,” Calvino says, “time is a form of wealth to be spent at leisure and with detachment.”
Colloquial expressions about the inconstancy of time reveal a profound insight into its perplexing malleability in conscious experience. We know that perceived time builds its own consequential rhythms against the incessant, monotonous, illusory beat of hours, minutes and seconds.