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Our perception of time is peculiar. We do not have an organ that measures time as we have organs for sounds, smells, or images. There are no time hallucinations or time illusions in the way there are visual or auditory ones. (Some have suggested that the whole experience of the passage of time is a grand illusion, but we need not worry about that here.)
The reason we don't talk about time hallucinations and illusions is not that our perception of time is always veridical; rather, it's because when time seems to us to pass faster or more slowly than it really does, we do not call that an illusion. While time passes at a constant rate of one hour per hour, we take it for granted that it doesn't always need to feel that way.
In other words, there is time, and there is our experience of time, and the two need not align. But why?
Over the Course of a Day
Our perception depends, perhaps most obviously, on the activity we are engaged in and on our state of mind. Time seems to pass very quickly when people are fully absorbed in the task at hand and are in a state that some psychologists have called “flow.” It appears to pass more slowly when we are bored, and more quickly when we are worried.
Consider a passage from Thomas Mann’s novel The Magic Mountain:
"There is a case of a passage of miners buried and shut off from every possibility of knowing the passage of day and night, who told their rescuers that they had estimated the time they had spent in darkness, flickering between hope and fear, to be some three days. It had actually been ten. Their high state of suspense might, one would think, have made time seem longer than it actually was, whereas it shrank to less than a third of its objective length."
Research offers empirical confirmation that anxiety makes it seem as though time is passing by faster. Perhaps, anxiety is incompatible with boredom and it makes it seem as though time contracts, much the way this happens when we are absorbed. By contrast, time seems to slow down when we wait with impatience. (Meditation practitioners may be able, perhaps, to produce in themselves a state of absorption and counteract the impatience as well as to "quiet" the worried mind and replace the unpleasant absorption of tenseness and agitation by calm focus on a neutral object of attention.)
In the Event of a Frightening Accident
There is also the curious phenomenon of time "dilation" or time’s "running in slow motion" during a frightening and life-threatening event. The case is a very interesting one. I know someone who experienced this in the course of a bad accident, and he reported that the type of “slowing down” involved is unique and nothing like the slowing down of time due to boredom, as when you wait in line with nothing to do. Rather, it was, he said, a feeling that everything was happening in slow motion—like viewing a tape of an event at half speed. (Interestingly, this type of experience is sometimes conveyed in movies also—say a character would see a threatening object approaching, and the object would be shown moving at slower than the expected speed.)
How and why that happens are good questions, and different answers to them have been proposed. One hypothesis is that we are thinking faster in those situations and that this makes it seem as though time is slowing down. According to another hypothesis, people take in a lot of new memories, and this makes them misremember their own experience.
My own hunch is that our tendency to experience time as slowing down in force majeure circumstances is a protective mechanism which allows us to calm down and act with clarity and without panic. But I leave a fuller treatment of the issue for another occasion.
Time Perception Throughout Our Lives
There is one type of pattern in our perception of time that we see systematically, a pattern that may well be universal: Time seems to pass more slowly when we are children. It does not matter what activities we are and were engaged in or how interesting or not our childhood was compared to our adulthood: Time seems to pass faster as we age, for everybody. Why?
I wish to suggest that there are three main reasons. The first is that adults do a lot of “mental time travel”—we are always thinking about the past or the future, and the present slips away unnoticed. In his Pensées, Pascal says, similarly:
"Let each of us examine his thoughts; he will find them wholly concerned with the past or the future. We almost never think of the present, and if we do think of it, it is only to see what light it throws on our plans for the future."
There is a good deal to say here about the effect of this tendency on our chance of happiness, but I have discussed this issue elsewhere. The important point for present purposes is that children do not, as a rule, spend time reminiscing or anticipating future events, because they don’t have memories that go far back, and they have little control over their future or clear idea of what it may hold for them.
The second point is that a year is a much bigger proportion of the life of a child than it is of that of adults. This may matter in the way in which our physical size matters to our perception of the size of other things. A small swimming pool might look like an Olympic-sized one to a preschooler, because it’s big compared to her. Similarly, a year in the life of a 6-year-old is 1/6th of the child’s life, but in the life of a 60-year-old, it is 1/60th. That matters. We are the measure of all things and from here, of the size of things.
There is a final reason adults and children perceive time differently. A child typically does not have life plans that she thinks she ought to realize before she dies, so there is no rush. She feels little pressure to check items off her bucket list, or realize her potential, or make something of herself. While an overly ambitious parent may think his kindergartner is behind somehow, no kindergartner feels that way.
A young child is typically waiting with impatience the arrival of adolescence and adulthood, vaguely feeling that she would then be able to make her decisions and carry out plans. An adult, by contrast, is not waiting with impatience for old age and not simply because old age does not sound nearly as fun as young adulthood: Adult often feel they have catching up to do. Hardly any of us, even the least ambitious, have done everything we wanted to in the time we’ve already lived. We feel behind not only on individual projects but on life.
An elderly tailor I used to go to said once that life was like a roll of toilet paper—each rotation is slow at first but gets faster and faster as there is less and less paper left. I knew just what he meant. You probably do too.
What is worse is that thinking about how quickly time is passing takes time. This thought itself—one that children do not have—distracts us from the present and both robs us of the opportunity to make the best of the present and makes it so that the present will fly by unnoticed. Time always passes quickly when there isn't much of it. And there is never a lot of time if we spend much of the time we have fretting about how little is left.
