Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, July 8, 1993 TAG: 9309020343
SECTION: EXTRA PAGE: 1 EDITION: METRO
SOURCE: Joel Achenbach
DATELINE: LENGTH: Long
A: It would stand to reason that every so often, maybe once every three or four months, just because of random mechanical failure, you'd fall down an elevator shaft and die. But for some reason the elevator always seems to be there, which is good, because as a person of dignity you don't want people knowing that your last words on Earth were something like, ``There's this great little deli over by the: woh-woh-woh- WOOOOHHHHHHHHH.''
Here's the key thing you need to know: The doors to the elevator shaft can only be opened by the doors on the elevator car. There's no independent mechanism to open the shaft (or ``hoistway'') doors. The doors are kept shut by a powerful spring. If you pry them open with a crowbar, they will spring closed again. Because there's no way to mechanically open them without the presence of the elevator car, you don't have to worry that one day you'll hit the elevator call button and have it mistakenly open the doors onto an empty shaft.
The motor that opens and shuts both sets of doors is on top of the elevator car. When the car gets to within about an eighth of an inch of the correct floor, the hoistway doors are unlocked electronically and simultaneously snagged by the opening car doors.
``It is the safest means of transportation in the world,'' says Jim Christensen, spokesman for Otis Elevator Co. ``Statistically it is safer than walking.''
That's right. Because of the manhole danger.
Q: Why does it just so happen that you are alive now, during this modern age?
A: We started wondering this back in '69. It was when Apollo 11 landed on the moon. We wondered: How come we're alive during such an interesting moment? Is it just plain luck? Surely, we thought, there have been billions of people who lived in much more boring times, when the only interesting thing to happen was, say, the invention of the dinner plate, or an unusually bad plague of boils.
The question is, should we feel special? Are we lucky to be alive during a time of rapid technological change and good dentistry?
The answer is: No. The reason you are alive today is what would be expected, according to statistical probabilities.
First, you have to realize that there are more people alive today than at any other time in human history - about 5.4 billion people. There have been roughly 70 billion human beings born since the appearance of Homo sapiens about 200,000 years or so ago. This means that about 7.7 percent of all human beings who have ever lived are alive today.
You would be mistaken to argue that we're lucky to be in the 7.7 percent and not in the 92.3 percent who are dead and gone. You could apply that same twisted logic to any point in human history. Instead, you should realize that we live in a time of high population, and it makes sense that we would find ourselves in such a moment rather than at a time of low population.
There's also nothing remarkable about watching the first moon landing. High population, like moon landings, is a function of modern technology. So you would expect that amazing technological things will happen when there are lots of people watching.
Here's a twist: Although there's nothing statistically unusual about seeing a moon landing, statistics do tell us that it's highly unlikely that we'll ever colonize outer space.
Why not? Because our ancestors weren't aliens from space. If it is easy for an intelligent species to colonize the galaxy, then most people in the galaxy, at any given moment, will be descendants of colonists.
``The interesting thing is that you and I are not having this conversation on a colony of some galactic empire. We're living on the home planet,'' says Richard Gott, a Princeton physicist who recently discussed this issue in a paper published in the journal Nature. It's statistically unlikely, he says, that we will just happen to be born on the home planet of what will become a vast galactic empire.
Gott bases his argument on the ``Copernican principle,'' which states that there's nothing special about our location in the universe or, for that matter, our location in the lifetime of the human species. For us to colonize space over many thousands of years would mean that we were, through pure luck, alive to see the beginning of a long and prosperous period of space travel. Even though that's exactly what most of us believe, the Copernican principle says we shouldn't be so presumptuous - in the same way that ancient astronomers shouldn't have presumed that the Earth was the center of the universe.
In fact, the Copernican principle states that human population will probably decrease radically at some point in the future. Not level off: Decrease. We don't have space to get into a full explanation of this particular statistical prediction, but suffice it to say that it echoes the warnings of environmentalists.
We ought to feel horrible about all this. But for some reason we don't. We're going to put our money on the long shot here. We're feeling lucky. Sometimes you just have to blow on the dice and roll 'em.
Washington Post Writers Group
by CNB