Digital Watches Are Still Cool, Though

I realize that over the last few months I've been writing this blog I have done more than my share of ranting about clocks and calendars, minutes and months, seconds and centuries. This will be the last time, I swear. Well, no, it probably won't; this is a particular obsession of mine, ever since I read Robert Levine's A Geography of Time a few years ago. I highly recommend it, by the way.

Here's the essence of the book. There are two kinds of time, body time and clock time. Body time is based on your body's natural rhythms and pace; clock time, obviously, is based on the arbitrary values we have assigned, as measured by certain natural processes like atomic decay and the Earth's orbit and rotation. The two have little if anything to do with each other, and yet much of our lives is organized around trying to reconcile the two. And that, of course, is not a good idea.

Our bodies like to follow routines, patterns. If you did not have a clock and did not have a definite schedule to keep, your body would still fall into a natural rhythm, and would stick with it barring any unforeseen circumstance: you would wake up at about the same point in the sun cycle each day after about the same amount of rest, you would be active or lethargic for about the same periods every day, you would get hungry at the same point, you would get sleepy at about the same point after a certain period has elapsed since you woke. It's a good system, because it is set by the interactions between our own metabolism and environment; if you live in a tropical area, you will naturally be more sleepy during the day and more awake at night, because night is when the temperature outside is most conducive to activity. In a colder environment, that will be reversed -- naturally. You get hungry about the same time because this is when you need the food energy, and when you have easiest access to food; if you do follow a work or school schedule, you have probably noticed that you feel hungriest on the weekends at pretty much the same time you get your lunch break during the week.

I wake up, every day, between 4:30 and 5:30 am -- an hour or two before sunrise. It takes me about an hour to get going, and then I have a period of time when I can be very productive. It usually lasts about two hours, until about 7:30, 8:00. Then I can still do physical things, but my brain wants a rest. I get hungry for lunch about 12:00 or 1:00, and then I want to nap until 3:00. Then I have another productive time until about 6:00, when I want to eat and then relax; I'm ready to go to sleep between 9:00 and 10:00 pm, two or three hours after sunset, during the spring.

Now enter the clock. School starts at 8:20 each morning, right when I'm ready for mindless labor. Lunch is at 11:20, ending at 12:00; classes continue until 3:00. I don't get home until about 5:00 most days. So I am forced to work when I am least productive, and forced to be mentally idle, usually going from home to school or vice versa, when I am most ready to think things through. But even this is manageable, because our body rhythms can adjust to the clock to a certain extent; over the last four years that I've been eating lunch at 11:20 I've gotten used to it, so now I usually feel hungry about then. I still can't eat anything large, since that makes me ready for a nice siesta, which is not a good pedagogical strategy. But the time of greatest activity for my brain doesn't pay any attention to the school bell; it just means I'm kind of stupid during some of my classes, and much quicker during others.

Then, as if that weren't madness enough, the time changes. Now, all of a sudden, my alarm clock, which is set for 6:00 and thus never actually goes off, has to pull me out of my last half-hour of sleep. I'm walking to school when the sun is still below the horizon, I'm not hungry when it's lunch time but I'm starving halfway through my after-lunch class. It does get me home in time to do some good thinking, but it means I'm not going to bed until later -- which just exacerbates my tired mornings. And my schedule is a fairly easy one; I think we all know that the change to and from Daylight Savings time, like jet lag and time zone shifts, wreaks absolute havoc on some people.

So here's the thing. Why can't I teach at 6:30 in the morning, and at 3:00 in the afternoon? Or, even better, from sunrise to midmorning, and then from midafternoon to just before dusk? Of course some students wouldn't be in the mood to learn then, but I feel pretty sure that there would be teachers who would prefer to teach from, say, midmorning to midafternoon; they could take the late sleepers while I get the early risers/nappers.

Put more interestingly: why can't we follow our own internal clocks? Is there any reason why we couldn't synchronize and syncopate our varied natural rhythms, instead of all of us trying to match some arbitrary system of ticks and tocks? Of course there isn't: several cultures around the world do exactly that. So does this system, our system, really suit anyone? Is anyone better off ignoring the body's demands in order to follow the demands of the clock?

Why do we have Daylight Savings time? I remember rolling my eyes at the anecdote about somebody saying that Daylight Savings time makes the day an hour longer; I'm sure all of us have heard some version of that and thought, "How stupid! Changing the clocks doesn't add an hour to the day. It doesn't change the speed of the Earth's rotation; how ridiculous. It doesn't actually change anything, other than the number on the clock."

Think about that for a moment. Then think about the question again. Why do we have Daylight Savings time, exactly?

It doesn't actually change the number of hours of daylight, or the number of hours of night. Nor does it, as most of us learned today, change our body's natural rhythms; it just makes us tired and crabby until we manage to adjust our internal clock to match the new schedule, just as arbitrary and unnatural as the old schedule. If I wake up an hour before sunrise every morning, that's an hour I am going to be turning the lights on, no matter what hour is on the clock when I do it. And if I do adjust my sleeping schedule to match the clock time, so that I get up at sunrise/6:30 am and leave the lights off, it isn't going to change the number of hours of sleep I need every night, and so I will most likely stay up an hour later -- and keep the lights on at night after the sun goes down.

So why do we have Daylight Savings time, exactly? Seems like there's no point to making arbitrary changes to the clock's time, since those changes don't actually change the speed of the Earth's rotation, nor its orbit around the sun, nor our body's natural pace. Changing the clock doesn't change time.