Time

Sunday, 24 January 2016, 20:07 | Category : Life, Mississippi, Nature, Philosophy
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greenwood_arches1

There’s an old cemetery that I’ve walked through on occasion – a couple of times when I was helping to clean up and plant some antique roses among the headstones, a couple of times when I was just walking around. The cemetery dates back to the 1820s, and holds the remains of several Mississippi governors and other notables, including those of Eudora Welty. There’s also a section of unknown Confederate soldiers. The cemetery lies in sight of Mississippi’s State Capitol building and other state office buildings, but it’s surprisingly unknown to many people. One gray January afternoon a few years ago I was wandering through some of the older parts of the cemetery and happened to notice something at the base of a large tree. When I looked closer, I saw that it was an old headstone.

tree_and_headstonegray

I’ve thought about that headstone many times since. It’s almost a parable about our relationship to the world in which we live. Or at least, a reference to Ecclesiastes Chapter 1:

What do people gain from all their labors
at which they toil under the sun?
Generations come and generations go,
but the earth remains forever.
.
.
.
What has been will be again,
what has been done will be done again;
there is nothing new under the sun.

In the end, the trees win. Time wins. Time always wins.

Watching Traffic

Wednesday, 10 October 2012, 11:35 | Category : Life, Philosophy
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I graduated from a small liberal arts college. I’ll get back to that.

This morning on the way to work, as I merged onto the Natchez Trace Parkway for the short segment that emptied onto the interstate, I began to look at the traffic (not for the first time) not as cars but as packets of information, flowing (or not flowing) on a network. Getting on the Trace wasn’t such a big deal; most of the traffic was merging, with just a few cars upstream. So except for the occasional ornery upstream driver who wouldn’t slow down and let you merge, things proceeded apace, which on this stretch of the Trace is 40 mph. A mile or so down the road, it gets more interesting, as you get off the Trace (which everyone has to do at the moment, because the Trace is closed at that point) and merge onto the interstate. You come into a lane on the far right, which will end in about 300 feet. You move to the left one lane, but that lane, in about 1000 feet, will veer to the right onto the bypass. So you have to move at least one more lane to the left to continue south. And if you’re smart, you won’t stay in that lane either, because another 1000 feet or so beings you to an interchange, with traffic leaving the interstate and more coming on. So it’s another move to the left, or maybe two, which would put you in the far left lane. This, you would think, would be the best lane if you’re going several miles down the road. Unfortunately, that’s most often incorrect. The middle lane of the three going south seems to often move faster, which flies in the face of reason – but Mississippi drivers don’t use reason when driving. Lane-changers are constantly moving from the center lane to the far left lane, which means drivers in the far left lane are then constantly having to slow down, because of course when you change lanes you have to then slow down just a little. This results in the center lane often having big gaps where you can maintain a decent speed, and the far left lane sometimes coming to a near-standstill. There is still a benefit in being in the far left lane – idiots changing lanes without looking can only come at you from one side (the right), and you have a small margin of safety if/when they do. But I digress – this is about traffic flow. Or really, about how I see networks everywhere. I was watching cars merge, and change lanes, and thinking about how networks behave when they get crowded, and how they don’t have packets randomly changing lanes – at least, hopefully they don’t. All highway engineers can do is design roads and interchanges, and then hope for the best. Networks can be designed, and then actively managed. We’d probably all get to work faster if the engineers could actively manage traffic.

Anyway, I said I went to a small liberal arts college, where I studied math and physics. One of my math professors considered teaching a class in queueing theory one semester. None of us, the small number of math majors, were really interested – we couldn’t see any reason why we would want such a theoretical class – so he dropped the idea. I wish he hadn’t, and I wish we’d been interested in taking the class. I sometimes think the world might make more sense to me now. Or at least, I might understand what passes for the underlying logic of things moving around me. Once again we find that youth is wasted on the young.

Doors, Computers, Tigers

Friday, 29 September 2006, 22:06 | Category : Philosophy
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Here’s where this mental exercise started… Loren got me interested in reading Space and Place by Y-Fu Tuan. More on that book later, when I’ve read further. My thought process began with a door, then ran through computers, and ended up at a tiger. As I read tonight, I happened to glance across the room. Not at anything in particular, just one of those random glances you sometimes make in the midst of a prolonged ponder. I focused on the door, about 12 feet away, the bookshelf beside it, then another door nearby. I thought about how my brain seemed to synthesize several responses to the scene in a package: the door is about 12 feet away, the wall is white, there are about 6 books on each shelf (it’s a narrow bookshelf). Then I thought about how a computer would “see” that scene, if it had a camera attached. I can grasp how it would characterize color. I can understand how it might deduct the presence of multiple books on a shelf, by an algorithm that would note the different roughly parallel rectangles formed by the book spines. But then I thought about distance. How would a computer know distance? Certainly, it could use a laser range finder – but in the absence of a direct measurement tool, how would it do this? Our brains, I’m sure, use a combination of experience and knowledge to perform a quick calculation – but even when there aren’t reference objects available, like the futon between me and the door, our brains can do a pretty good distance calculation in most situations. I don’t know how a computer would do this type of intellectual gymnastics. Then I thought about tigers. Tigers are very good at leaping. Along with many other things, I learned this from Winnie The Pooh. And the Discovery Channel. And Wild Kingdom. Tigers leap very well. But I don’t think they calculate distance. Tigers don’t say to themselves “Let’s see, the deer is on top of that earthen bank, the bank is about 13 feet away, I have to clear a 3 foot shrub…”. I think tigers think effort. They don’t know how far they need to jump, they just know how hard they need to jump. I’ll admit I have no scientific basis for making such a statement, it just seems to me that distance is a concept that tiger brains don’t handle. They don’t experience the world that way, in the same way that we don’t calculate the distance to the basketball goal, we just know we need to shoot the ball that hard. We can, however, stand on the basketball court, look at the goal, and estimate that we are 18 feet away. Same physical setting, 2 different ways of experiencing it. When we shoot the ball, we’re tigers. When we mentally calculate the distance, we’re people. But neither of these experience sets is applicable to a computer. So I go back to wondering how a computer would devise a value for a distance. If you have knowledge of how this is done, feel free to enlighten me. Just remember, no laser range finders.