1. Read the Narrative below.
2. Answer the following questions.
3. Respond with comments to at least two other students’ answers.
The Scientific Method
Thomas Kuhn, the great historian of science, writes that there are two kinds of science: Theoretical Science and Normal Science. So, to use medicine as an example, two doctors might graduate in the same class at medical school, both with top grades. However, they choose two different paths for their careers.
The first one always admired his childhood family doctor, which is exactly why he went into medicine. He chooses to open his own family medical practice back in his own hometown. He uses all of his knowledge to treat families with colds, the flu, tonsillitis, and more serious problems, such as heart disease and cancer. He, of course keeps his knowledge up-to-date with continuing education courses.
His classmate has never much cared-for the idea of family medicine, but she loves involvement in the development of medical science in the laboratory. She gets hired by a big teaching hospital as a researcher, conducts many Lab experiments, and writes papers about new techniques and outlooks that she and her colleagues develop. She is, in fact, questioning all the time the boundaries of medical science and, in fact is constantly pushing knowledge beyond known boundaries.
The first doctor practices Normal Science. He takes care of a waiting room-full of patients each day, curing their illnesses. The second doctor is a Theoretical Scientist, working mostly to come up with new ideas, and new theories. They each represent one of the two sides of science.
So on the theoretical side, where do hypothesis come from? Dr. Villa, now Dean of the College of Arts and Sciences, suggests that they are ‘educated guesses.” That is, that people with a great deal of knowledge in a particular field, would offer guesses as to the best explanation for whatever data are under study.
To illustrate this phenomenon, we can make good use of examining the most earth-shattering of Scientific Revolutions: the Heliocentric Theory. The first three great astrophysicists of the Renaissance, Copernicus, Galileo, and da Vinci, were in the process of inventing, and building, better and finer telescopes to make their astronomical observations. They were superb scientists, with great attention to detail, and they also were master mathematicians. They observed the orbits of the closer planets, in much finer detail than was possible with the naked eye. They then wrote down their observations scrupulously, and calculated mathematical equations on the observed arcs of those planets. As these data were being examined, they began to realize that, if their observations were true, the earth could NOT be the center of planetary orbit, and probably not the center of the universe either, both the prevailing “educated guesses,” by the best-educated Europeans at the time.
It was Copernicus who decided to promulgate this idea. All three of them knew it would mean big trouble. It was called Heliocentric Theory, for “Helios,” the Greek work for Sun. In the best educated guess, with the Humans in charge of the center of planetary orbit, and probably of the Universe, the Humans had charge of their Biblical rightful place as “Created in God’s image.” Now, all of this was out the window. Now the earth was only the third rock from the Sun. This threatened all of the revered learning handed down from Egyptian, Greek, and Roman texts. These three great scientists paid greatly for this Heliocentric Theory, spending most of their adult lives either in Prison, or under house arrest.
The fact of the matter is that, the more outlandish. the more unbelievable a theory is, the more world-shattering it may be. A hypothesis can come from anywhere. It can come on us, waking us suddenly in a dream. We could suddenly “get the answer” when reading a comic book. In many cases, both in ancient times and today, it is referred to as “Prophetic Insight.”
Science is not bad-smelling labs, and beakers and test tubes, although there may be some of that. It a form of purposeful linear thinking. Science is a hypothetico-deductive framework for testing hypotheses. No matter where the theory started, it will need to go through a process of: 1) data collection; 2) deduction of test implications which must be true if the hypothesis is true, and; 3) the testing itself. Now, we learned those steps, IN ORDER, in 4th grade science class. But the logic of hypothesis testing is a-temporal, that is to say, it is NOT required to follow a strict time sequence. Data itself has no memory. So, data used to create an hypothesis, is not so contaminated that it cannot be used to test the hypothesis.
Wellllllll,,,,,But doesn’t that lead to circular reasoning? If we collect some data that we are now trying to explain by our new theory, and then we use the same data to test our theory, won’t it always come out true? Correct! That is called a circular argument or a tautology. Your theory will ALWAYS be found true with this procedure, but you will always be wrong. While it is true that the original data that formed the hypothesis MUST be included in the later tests of validity,those data can NEVER be the ONLY data used for the test.
This is the old logical/philosophical concept of necessary and sufficient data. The original data not only CAN BE allowed in the test of validity, it MUST be used. That is to say, it is necessary. However, it is NEVER SUFFICIENT by it self, for the test, or we wind up in the circular argument. We always need to gather, and use, new data to include in the validity tests.
In fact, if there are two theories (or more!) competing as the favorite explanation of our data, we have a two-part test to decide the winner. The theory: 1) must account for all the known data, and; 2) must be the simplest one.This latter part, known as the Simplicity Criterion, is also called Occam’s Razor, named for the great 14th century Natural Philosopher, William of Occam. It is called a razor, because it cuts through the layers of often redundant, and most always unnecessary and unprovable, arguments, such as: “How Many Angels can Dance on the head of a pin?” As to the first part, you cannot ignore previously-collected data. If the research was honest, and the work done accurately, the data needs to be included in any new theories. As an example, any work done on planetary rotation would have to include the early work of Copernicus, daVinci, and Galileo,even 500 years ago.
Another example of the simplicity criterion, is a scenario that was presented in the first Psychology course that I ever was in. The CEO of a large firm, worked in an office in a skyscraper office building in Manhattan.. He would come in for work each morning to find the top of his desk completely neat and straightened, and all the pencils were sharpened, and in straight rows. It was posited that one theory for how this happened, was that there is a species of pencil-sharpening gnomes, about 3 ft. high, with pointy ears, and beards, and curly-toed shoes. At night, several of them at a time would surreptitiously enter the offices of higher corporate executives in New York, and do this good deed, something like how Santa Clause gets into your houses on Christmas Eve.
An alternate possibility, a competing theory, is that the Administrative Assistant would get to work each day, about 20 minutes before the CEO, straighten the desk, and sharpen all the pencils. In comparing the two theories, it was pointed out that there is nothing wrong with the pencil-sharpening gnomes theory, except that it violates the simplicity criterion. We can see the Administrative Assistant sitting there in the next office, but no one (to my knowledge) had ever seen these little gnomes, with pencil-shavings still in their beards.We have to go just one more step to create them in our minds, while the Administrative Assistant is right there. Otherwise, it would be a dead heat, but because of Occam and simplicity, the gnome theory loses.
Finally, especially where there are a number of competing hypotheses, we like to know the strength, quantitatively, of each one. The scientific process demands that we derive from each theory, a series of “test implications,” that must be found to be true, if the hypothesis is true. Now, the size of that series of test implications is important quantitatively. If we can only come up with 3 test implications for our theory, but the competing lab, with a competing hypothesis, comes up with 7 implications, they have the stronger hypothesis. So, to measure the strength of the confirmation of any hypothesis, depends on 3 factors: 1) The number of implications that can be confirmed; 2) The independence of the implications, and 3) The logical completeness of the implications.
First Science Module Questions
1. Where can scientific hypotheses come from?
2. In the case of the pencil-sharpening gnomes, what indicates that it was the Administrative Assistant who did the sharpening?
3. What does the strength of the confirmation of an hypothesis depend on?