November 20, 1992

Luck: Good and Bad

Accident, n. An inevitable occurrence due to the action of immutable natural laws.

Ambrose Bierce, 1906

It's one o'clock in the morning and Phil Friendly, a traveling salesman, is taking advantage of the lack of traffic and the cooler weather to go the 400 miles to his next stop. Phil is a careful driver and he has his cruise control set at 55 miles per hour as he travels west down the four lane highway.

At the same time, Joe Souse is leaving a bar. He staggers to his car, starts it, and goes north traveling at about 50 miles per hour on a two lane road. At the point where the road intersects with the highway that is being traveled by Phil Friendly, is a stop sign. Joe will ignore that stop sign and will cross the road at 50 miles per hour. He has done it many times before and has never even had a close call at that hour of the morning.

Since these two vehicles are the only vehicles on the road at that hour of the morning, within a 30 mile radius, what is the probability that they will meet at that intersection? The chances are extremely small; perhaps in the neighborhood of one in a million. But what are the consequences of those two cars meeting at that intersection?

On the following day, the newspaper has a story about the death of Phil Friendly and Joe Souse in a "tragic automobile accident". Two people killed as a consequence of them both being in the same place at the same time despite the great odds against that happening. At this point in time, the probability of those two cars having met at the intersection is certainty. It wouldn't have mattered if the chance of it happening was one in a thousand trillion, once it happens it's for sure --certain. Once you're dead, you're dead!

If you think that just because the odds of something happening are astronomically small, that it won't happen, think again. The number of sperm in a single ejaculate are 250,000,000. If any other sperm but the one that reached the egg had reached it, you wouldn't even exist. If we continue this reasoning back through your family tree, the probability of you existing at all would be, to all intents and purposes, almost zero. (This was suggested by the gospel of Dr. William Cosby.)

So, if you are born, and don't get killed in an accident or get some deadly disease, and you die quickly in your sleep at 90 years of age, one might say that you are a very lucky guy, even though you lost the lottery more than a thousand times. On the other hand, you can have a miserable life, loose children, be sickly and die a slow agonizing death at 40. One might say that you have had very bad luck.

In short, the only time that probabilities are important are before an event happens. When you hold that royal flush in your hot little hand, who cares that the odds were only 1 in 649,739 that you would have drawn it.

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