I write this while on graveyard duty at the treatment center.
Having a job that demands round-the-clock availability really makes you realize how strange social attitudes about time and work really are. Admittedly, I've had plenty of cause to think about this before due to recurrent insomnia and the inevitably chaotic schedule of academia, but having an actual "legitimate" job with a chaotic schedule raises the issues far more sharply.
Our society operates largely on solar time; it is expected that people will wake up in the morning and sleep at night. People who choose to do otherwise are generally considered not only odd, but off somehow: unhealthy, antisocial, irresponsible, potentially criminal. Is there really any good reason for this?
Remarkably few people in our society actually need to operate on solar time. Remarkably few activities actually depend upon solar time. Agriculture, surely. Solar power generation. Earth-bound solar astronomy. Hunting. Nothing else I can think of. Technology has separated us enough from natural cycles that just about everything can in principle get done at just about any time of day. (And this is hardly a new thing, either.)
I can think of two major reasons for continuing to operate on solar time: that people prefer daylight to nighttime, and that it is important for various reasons to have (just about) everyone operate on the same schedule.
The first of these reasons is legitimate, to the extent that it's true, but I wonder about its source. Do people really have such an attachment to daylight itself, or is it that they're attached to having a "normal" schedule? Having to stay up all night may be bothersome because you never see the sun, or it may be bothersome because it disrupts your ability to live a normal life in all kinds of ways: all the shops and restaurants are closed, few other people are awake and sociable, etc. If it's primarily the latter, then it should count as a reason to get our society away from a solar clock, not to keep it on one. If we lived in a 24-hour society, it would be perfectly normal and un-bothersome to be awake at 2:00 AM. I think it's far more difficult than it might seem to disentangle these factors. Why, exactly, do we miss the sun so much when we don't see it for days at a time? Is it just that the sun is so beautiful we can't live without it? The moon and stars are at least as beautiful. Why do we fixate so much on the sun? Certainly graveyard workers miss the sun, but if working graveyard were totally normalized, maybe they would get used to this. Maybe day shift workers would come to miss the moon and stars, and envy graveyard workers.
(There is the argument that sunlight is important for human mental and physical well-being; there are various studies trying to prove this. I've always doubted that these studies have sufficient controls, though, since, given the current state of our society, there are all kinds of reasons--class, for instance--for graveyard workers to be less healthy than "normal".)
The second point, that it's important for society to be organized around one particular sleep schedule, seems problematic to me. (It's also not, in itself, an argument for solar time, obviously.) I don't see why a society couldn't have a 24-hour schedule, with people working all kinds of jobs at all times of day, and still function perfectly well. There would be various advantages to this kind of arrangement: it would create lots of jobs, obviously; it could, conceivably, raise productivity levels; it might reduce crime, since it would mean that more people were out and about at night. If a community is too small to operate all businesses 24 hours, that's one thing. If it's a major or even mid-sized city, I don't see why it's impossible.
Some of the world's greatest cities--New York, for example--are already essentially on 24-hour schedules, and this has not led to any massive breakdown in the social fabric. Is there really any good reason the rest of us can't join them?
At the very least, I feel, we should get rid of the late-night stigma. Many of us have no choice but to keep "odd" hours, and don't deserve to be stimatized. And why can't we just accept the legitimacy of people's lifestyle choices? This is supposed to be a liberal society, dammit!