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President's Commentary (Winter 2004)
  By Jim Nelson
  Announcer, Vol. 34, Iss. 4

What Is Science?

Recently I was asked, "What is the scientific method?" As the thermal energy in my feet fled, I realized I didn’t have the clean answer that my inquisitor expected. After rambling around for a while I presented the following model as a representation of "science."

Science is one way of trying to make sense out of the world that we experience. Clearly it is not the only way. For example religion, philosophy, traditions, art, etc., are other ways that people make sense of the world.

Collection of Facts:
One view of science is that it is a collection of facts or information about the world. As the number of facts becomes overwhelming to remember, people have found patterns that relate these facts together. These collections of facts and the relationship among them are variously called natural laws, theories, principles, etc. Observing how gases behave leads to a number of facts. Consider these examples. When the temperature of oxygen gas in a closed container is increased, the gas pressure inside the container increases. If the same gas is placed into a flexible container (e.g., a balloon) the size of the balloon increases. If the inflated balloon has an opening the gas inside comes rushing out. These facts can be observed for many other gases. Eventually someone suggested that all gases act this way. It is interesting to note that what all gases have in common is the space among the atoms or molecules, and in a sense the gas laws describe the space that is common for all gases and not the individual atoms or molecules that are different for each gas. Eventually someone else suggested that these behaviors can be "explained" if we assume that gases are really a collection of very tiny particles that are moving around randomly at high speed. This pattern that relates many facts about gases is then given the exalted title "Kinetic Molecular Theory."

Once we understand the theory, we are able to forget many of the facts. The individual facts can be reasoned out using the theory. Clearly these facts and the theories that tie them into patterns is one aspect of what we mean by science.

In the diagram below this is portrayed as the left extreme of a spectrum.

Process for Uncovering the Facts:
Another answer that could be given is that science is the process used to uncover the facts and theories about the world. This is meant to represent the methods used by scientists, or anyone else for that matter, that is used to uncover the facts and the connection between facts that we call theories or laws. This process has many attributes that can be identified. But it is not possible to state the process as a recipe as implied by the phrase "The Scientific Method." I believe that a goal of science education is to move our students toward the right in the spectrum in Diagram #1.

One of these attributes about the process of science is that anyone can do it. One difference between magic and science is related to this "anyone" principle. In magic the goal is to have a limited number of people who have access to how it is done. The opposite is true of science. One of the aspects of science is to make it possible for anyone to challenge the facts and theories or to verify the observations. In short, science tries to make it possible for anyone to know how it is done. This view of science is very important to a democratic society that depends on an educated population. Too much education is the enemy of the dictator.

Another aspect of science as a process is a belief in reproducibility. If I make an observation and then you make an observation under the same conditions now or at any time, the results will be the same. If the results are not the same, then science suggests that the conditions were not the same. In short, science as a process suggests that the same cause will produce the same effect. Since we know that cause and effect is based on probabilities, sometimes we have to make many observations to find the general rule underlying phenomena.

Questioning the Facts:
Yet another aspect of science as a process is the skeptical attitude. This attitude develops the belief that you should be able to understand yourself and not have to rely on experts. Recently I saw a question in a book. The question was to place the following in order: atom, element and molecule. My immediate thought was that they already were in order — alphabetical order — but I know that was not what the author wanted, so I looked in the back of the book for the answer. The answer given was that the atom was the smallest, followed by the element, and finally the molecule.

Here we have an example of "not-science" at both ends of the above spectrum. Not only was the factual answer wrong, but also the process of science was missing. My take on the quantum theory makes it impossible to specify the size of an isolated atom. Considering the bond lengths of various molecules that contain that atom permits us to approximate a value that is taken as the atom’s radius. In any case it is difficult to compare the size of an isolated atom and that same atom in a molecule.

As to where the word "element" should appear in this, I have not a clue. An element is a substance, which contains only one kind of atom, and thus it can be as small as an atom to something large enough to see. I am distressed that the author of the book question not only had the facts wrong, but also did not have enough scientific literacy to doubt the simple answer the book presented.

I know I have made many mistakes like this in my career, but in my teaching this year, I hope that both my students and I will grow in not only the facts of science, but also in our ability to use a scientific process in and out of school.

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