December 13, 1991

Theory and Fact

When you know a thing, to hold that you know it, and when you do not know it, to admit that you do not --that is true knowledge.

Confucius, c.500 B.C.

It was Saturday morning in Washington, D.C. Lu and I were visiting with one of our kids and a four month old grandchild. We were sitting in the living room and, while Lu was bottling the baby, I turned the TV on. At home, I never turn a TV set on in the morning. There were at least a dozen channels with cartoons, one with Superman and one with a program on the atom. My choice was the atom or nothing.

I was glad that I watched that program, because it presented the current theory of the structure of the atom. It was different from what I was taught about the atom some 40 or 50 years ago. It gave me an opportunity to reflect on theory and fact; a favorite topic of mine.

The existence of the atom is a fact. It is no longer a theory. When it was first proposed, not only was it a theory, but it was a highly controversial theory. In time, competing theories dropped by the wayside. Now the atomic structure of matter is used to predict chemical combinations, make new materials and in many other ways. Predictions based on atomic theory, while not certain, are very good; like predicting tomorrow's weather. Not only that, but atoms can now be seen with a new scanning electron microscope. --Miraculous, isn't it?

When I studied physics in high school, the electrons were thought to orbit around the nucleus like the planets around the sun. Later, they were supposed to orbit in three dimensions and the sci-fi pictures of it were used on chemical companies corporate logos. Now physicists are prepared to admit that they really don't know what the electrons do around the nucleus and present probability plots of where an electron might be at different times.

This is a case of learning that we actually know less than we believed; a not-too-common phenomenon in science. Scientists are a lot more reluctant to admit that they now know less about something than they did last year. Fortunately, old scientists die and the new scientists can genuinely enjoy disproving the theories of the old men.

We know a heck of a lot more about chemistry than we do about biology. That's because when you have a glass of distilled water, it contains only one kind of substance; while if you look at a cell, it contains who-knows-how-many substances, most present in tiny quantities.

The people who make the discoveries go beyond what we supposedly know, to what is not known; or to what we know that isn't so. --And the people who "know it all" die, and science progresses.

It would be nice if this happened in other spheres. It seems to take much longer to change people's ability to live with each other. Maybe that's because people have been around for a lot longer than scientific theories. People also establish institutions called governments and religions, which guard the theories against those who would suplant them with others.

Now the science program has been replaced by a video of The Little Mermaid. My grandson is rocking in an automatic swing and I am typing on my portable computer. I reflect on what all this will do to his undeveloped mind. Oh well, we are all experimental animals in a random world that is full of untested and wrong theories. I not only don't have the answers, I don't even know what the important questions are.

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