April 3, 2003 (Ira Pilgrim)

Natural Laws

As long as we are lucky we attribute it to our smartness; our bad luck we give the gods credit for.

Josh Billings

The word "law" has many different meanings. We all know that certain laws of conduct are passed by governing bodies and that they are codified rules of behavior that govern people. They can be different in different countries. The laws that are almost universal are based on the golden rule, that a person should not do to others what he doesn't want them doing to him. Not obeying a law, and getting caught, can lead to punishment.

When we talk about "natural laws," it is less clear. I have read statements that say that something behaves in such-and-such a way because of Einstein's theory of relativity. I have also heard statements like, "When you throw something up into the air and it comes down, it is because of the law of gravity." Of course, everyone knew, long before the principles of gravity, or even the word "gravity," that when you threw something up, that it would come down. In other words, the law(s) of gravity don't make anything happen or not happen. What Isaac Newton, and those who came before and after him, did was to explain how physical objects behave. That understanding of how gravity works helped a good deal in making space travel and artificial satellites possible.

The Laws of Chance explain the frequency of card combinations, or numbers on dice, that can be expected with an immense number of coin tosses or deals of card; but those laws don't make anything happen. It is still possible to win the lottery despite the fact that the odds are very much against it.

I have had a course in statistics and perused a number of books on the subject, but I somehow failed to understand the explanation of the most basic principle of all; the principle of randomness. It refers to the fact that many events occur the results of which can't be predicted. Those events have a theoretical frequency. For example, if you toss a coin in the air there are three possibilities: it can come up heads, it can come up tails, or it can stand on the edge. Even though a tossed coin landing on its edge and staying that way can happen, and I once saw it happen, the chance of it happening is so small that we can ignore it. We know that the probability of a head is one half, or 50% and tails is also one half, or 50%. From this simple concept, almost all of probabilities can be calculated. How often could you expect two heads or tails in a row; or three or four or five etc.

I used to ask my class if I tossed a fair coin 5 times and got 5 heads, would the probability of getting a head be greater or less than 50% on the next toss. Most people would say it would be different, even though there is no conceivable way that the first 5 tosses could affect the 6th toss. Many people believe that a person can have a run of good or bad luck, and he can. However a run of bad or good luck can only happen in the past. You can't make a run of good luck happen unless you cheat.

If I feel lucky I know that it is an illusion, so I do something until the feeling passes. To act on that feeling would be just plain stupid.

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