The Scientific Method

My recollection of the Scientific Method is that it is a process where, after observing some phenomenon, a person derives an explanation for the cause of that phenomenon. Next, the person develops the explanation into a more formal statement called a hypothesis. The person then attempts to disprove the hypothesis. If the person fails to disprove the hypothesis, the hypothesis is then said to "hold" , meaning that it has not yet been disproved. If a hypothesis continues to "hold", then it may later become a theory. A theory never becomes fact and a theory is never believed or considered to be true because some other person may perform an experiment in which the theory does not hold, at which point the theory is either thrown out or modified to take into account the conditions in which it doesn't work.

A theory is simply the best explanation that we have at this time for the observed phenomenon that caused some person to come up with an explanation in the first place. A theory is not, and may never become, a fact. In fact, in science there really is no such thing as a fact, if by "fact" one means something that is indisputable regardless of circumstance. It is this fact that makes our Scientific Method so wonderful. The Scientific Method acknowledges that we humans do not truly know about anything in our world; we only have a best guess at this point in time about our world, and tomorrow we will probably have a better guess. In other words, we are never right, we may only ever be, hopefully, less wrong.

An example of the above occurred in my high school biology class. When I took the class, the text book being used to teach the class was brand new, meaning that it had been printed that very year. On our first day of class I sat there with my text book open and the teacher stood at the front of the class, held his copy of the book over his head and said these words, "Everything that I teach you from this book will be proven wrong within the next ten years." My jaw dropped; I finally began to truly grasp the enormity of the journey of scientific discovery.

The above paragraphs are what I remembered from many many years ago. To test my memory, I turn to two authoritative sources. The first source is my college physics book "Physics for Students of Science and Engineering" by A. L. Stanford and J. M. Tanner of the Georgia Institute of Technology (c) 1985 ISBN: 0-12-663380, pages 1 - 2.

"Physics is a natural science. It is one of humankind's responses to its curiosity about how nature works, about how the universe is ordered.
Like other modern natural sciences, physics has evolved to become a logical process based on the scientific method . This method is rooted in a philosophy that recognizes no truths and embraces no dogma but seeks to be completely objective and practical. The scientific method may be considered an investigative process composed of three parts:

  1. Physical processes are observed and measured both quantitatively and qualitatively. This step necessarily includes the conception and definition of appropriate quantities by which measurements may be made.
  2. A hypothesis is offered, usually in the form of a general principle or a mathematical statement of relationships between physical quantities (time and distance, for example). These principles or relationships can be used to predict the results of other similar physical processes.
  3. The hypothesis is subjected to experimental tests of its validity. Its predictions are compared to actual measured values.

Hypotheses proposed according to the scientific method are retained only if they enjoy continued and unfailing success. A single instance in which a hypothesis fails to predict successfully the outcome of a pertinent, repeatable experiment requires either rejection of the hypothesis or its modification to rectify that failure. Throughout the history of science many hypotheses have been discarded, and many have been changed. Those that have enjoyed some measure of success but are without extensive experimental verification over a long period of time are referred to as theories (those that have not had some success are not referred to at all). Hypotheses that have withstood successfully the repeated and diverse trials of experiment are accorded the title law, but even the most venerated laws of physics are not considered "true" by scientists. Laws are, along with all the tenets of science, acceptable only as long as they continue to coincide with measurements of physical processes. Scientists do not "believe" the laws of physics; they merely use them in very practical ways, maintaining a healthy skepticism that permits continual checking of current laws and theories and encourages speculation about new hypotheses. In this way the scientific method provides a rational approach to an intellectual and logical comprehension of natural phenomena."

From the above description of the Scientific Method, it appears my recollection was not incorrect. One point that is missing from the above description is that when subjecting a hypothesis to "...experimental tests of its validity", those experiments are to be negative tests. In other words, those experimental tests of validity must attempt to disprove the theory. It is a very well known phenomena that when someone wants to prove something they invariably will. So the Scientific Method does not ask scientists to prove anything, it requires them to try to disprove everything. The second source that I cite below brings this point out clearly. My second source is from which I quote below:

"In the twentieth century, a hypothetico-deductive model for scientific method was formulated...:

1. Use your experience - consider the problem and try to make sense of it. Look for previous explanations; if this is a new problem to you, then do
2. Conjecture an explanation - when nothing else is yet known, try to state your explanation, to someone else, or to your notebook.
3. Deduce a prediction from that explanation- if 2 were true, then state a consequence of that explanation.
4. Test - look for the opposite of that consequence in order to disprove 2. It is a logical error to seek 3 directly as proof of 2. This error is called affirming the consequent.

This model underlies the scientific revolution. One thousand years ago, Alhacen demonstrated the importance of steps 1 and 4. Galileo (1638) also showed the importance of step 4 (also called Experiment) in Two New Sciences. One possible sequence in this model would be 1, 2, 3, 4. If the outcome of 4 holds, and 3 is not yet disproven, you may continue with 3, 4, 1, and so forth; but if the outcome of 4 shows 3 to be false, you will have go back to 2 and try to invent a new 2, deduce a new 3, look for 4, and so forth. Note that 2 can never be shown to be absolutely true by scientific method...; only that 2 can be shown to be absolutely false by scientific method. (This is what Einstein meant when he said 'No amount of experimentation can ever prove me right; a single experiment can prove me wrong.')"

Putting the two together reaffirms my memory of the Scientific Method. I highlight again the preeminent philosophy of the Scientific Method is that nothing is proven and nothing becomes fact. The best way to understand science is that it is man's continual effort to prove that what he knew yesterday is wrong. It's the ultimate admission that we don't know anything. This is exemplified by the quote from Einstein shown above: "No amount of experimentation can ever prove me right; a single experiment can prove me wrong."

As defined above, science recognizes no truth at all. If anyone ever tries to tell you that something is a "scientific fact" or that "science has proven [ insert anything here]" you can confidently know that they are wrong. If the person making such assertions is in a position of authority or presenting themselves to you as knowledgeable of the subject matter, then I suggest you question their motives for making such statements. What does this person have to gain by attempting to mislead you? Money? Power? Prestige? It could be that they're just ignorant. Take the opportunity to educate them.

Science does not, has never, and will never prove anything, hence science does not produce facts. Science only hypothesizes plausible explanations for natural phenomena and then tries to discount those explanations. Any other process may be religion or philosophy or garage logic or a bar room parlor trick, but it is not science.

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