AV: Scientific Methods

AV: Scientific Methods and Values

LAB 1

HOW SCIENTISTS WORK:

THE SCIENTIFIC METHOD

The scientific method is a way of solving problems. It is useful in the laboratory, in the shop, in the home -- in the everyday affairs of life. Whether or not you specialize in science, you will find use for the procedures of the scientific method in solving your problems, practical and philosophic. The best way to appreciate and understand it is to apply it. The scientific method involves, primarily, the formulation of ideas on the basis of a relatively small amount of knowledge, testing the correctness of these ideas by securing more facts by observation and/or experimentation, arranging the facts observed in some orderly manner to determine relationships, and then drawing logical conclusions.

Although this broad definition does not mention the experimental method, it should be emphasized that it is an important way to obtain facts. However, we should make it clear that the scientific method is not limited to experimental procedure; on the contrary, observation rather than experimentation should probably be considered the basis of science. While mere observations in themselves may not be significant, observed facts correlated and intelligently interpreted often give rise to important generalizations. In fact, some branches of science such as astronomy have few opportunities to apply experimentation in the gathering of facts. On the other hand, sciences such as chemistry, physics, genetics and physiology are largely experimental. Observation and experimentation are the data-gathering tools of the scientist.

Question 1: What is the scientific method?

Question 2: What is the real basis of science?

Question 3: Why do you suppose experimentation has played such a small part in the science of astronomy?

LAB OBJECTIVE:

To understand the practices and attitudes utilized in the scientific pursuit of knowledge.

PROCEDURE:

Small group investigation and discussion.

I. The Scientific Method

A. Basic steps in the scientific method:

1. Recognizing and Stating the Problem - The problem at hand must be recognized, and as clear a statement or question as possible should be made defining the problem that requires solution.

2. Collecting Pertinent Information - Preliminary studies, usually involving library and internet work, should be made in an effort to assemble all known facts pertinent to the problem.

3. Formulating a Trial Hypothesis on the Basis of Limited Information - On the basis of information obtained from preliminary studies, a hypothesis should be made. A hypothesis is a tentative explanation of a problem. It is a mere trial idea, a possible solution to the problem. A good hypothesis requires at least two things: information and skill in making hypotheses.

4. Testing of the Hypothesis - This is accomplished by applying the results of all known investigations and/or by controlled experiments and further observation. In a controlled experiment, the variables (temperature, food, light, etc.) are controlled as closely as possible. This allows the investigator to test the effect of varying one factor at a time. If the hypothesis is not confirmed by the first experiments, other hypotheses need to be formulated and tested.

5. Organizing and Coordinating the Data for the Purpose of Analysis and Interpretation of the Facts - In other words, analyzing the results. Sometimes it is possible to organize the information in the form of tables and/or graphs that make it easier to see relationships and draw conclusions concerning the validity of a hypothesis. This means arriving at a decision based upon the facts obtained and involves checking the hypothesis. If the data of many experiments or observations agree with the hypothesis, then it may be concluded that the working hypothesis is correct.

6. Testing for Accuracy and Forming a Conclusion - Applying conclusions to other situations involving the same problem.

Question 4: Why should library work usually be preliminary to any scientific study?

Question 5: What is a hypothesis?

Question 6: How may hypotheses be tested?

Question 7: How may one conclude that a hypothesis is correct?

B. The Tactics of Investigation: The Black Box

One important objective in science is to devise explanations which have predictive value -- explanations which can be applied to general classes of situations and which predict some results of some given sets of conditions. Obviously, if predictive value is used as a criterion, not all explanations are equally good. An explanation based on some omniscient or omnipotent demon is simple to devise but not especially predictive. Unless the demon is constrained by some set of rules, one can't really predict what he will do next. And if one has the rules, then the demon, in a formal sense, is unnecessary: the rules themselves are the explanation. Unfortunately, concocting rules proves, as you will see, more difficult than devising demons.

Question 8: Why should a scientific explanation be predictive?

In this exercise you will be presented with Black Boxes. The original contents of each box (shoes, cigars, etc.) have been removed and replaced by some other object or material. A display of materials or objects currently occupying the boxes will be provided by your instructor. The problem is to predict what you would find if you were to open the box. Observations can be made in any fashion -- sound, smell, touch -- the only important limitation being that experiments must be non-destructive. The measure of success is the precision with which the contents of the box are described. Try to keep track of your different approaches to the problem so their relative usefulness can be judged after the box is opened.

For the initial attempt, the following format is suggested. Working in groups of four or five, spend no more than fifteen minutes on a single box. One person should act as a recorder and take down any conclusions which enjoy near-unanimity, along with the evidence and the arguments supporting them. The recorder will probably spend most of his/her energy trying to get the team members to phrase their findings in some precise and succinct form, rather than accepting explanations involving "several thunkers and clankers". When the instructor observes that science has lurched forward sufficiently, the investigations will be halted. At this point the recorder for each group will be asked to report briefly to the class on the findings of the group and the evidence supporting them. Following each report, the boxes should be opened in the harsh glare of public gaze.

Besides the initial set of boxes, another somewhat more challenging (!) group is available. If time permits, your instructor will arrange a competition between the groups. (If you think science is always noncompetitive, guess again!)

By this time, you have undoubtedly noticed that certain approaches seem to be more useful than others. Do preconceived ideas play any positive role, or are they always traps? Ideas of how progress can be maximized have been formalized by previous investigators and philosophers of science, using concepts such as hypotheses, crucial tests, predictions, confirming evidence, inferences, sampling, repeatability, degree of certainty, and so forth. We will leave it to you to explore the applicability of these concepts to the Black Box exercise just completed.

Question 9: Did some in your group seem consistently better at guessing than others? Why do you suppose that is?

Question 10: Which approaches seemed most useful? Which yielded the poorest results?

Question 11: Assuming you had unlimited access to laboratory equipment and techniques, what tests could you devise which would aid you in determining the contents of the black boxes?

C. Scientific Attitudes

To do science requires more than simply following a neat set of steps in problem-solving. It also requires a particular way of looking at problems. There are certain attitudes associated with the methods of science that play a key role in this way of approaching a problem. Listed below are some of the attitudes that scientists generally agree should be associated with scientific inquiry.

1. A Sensitivity to Problems - The habit of an inquiring mind should be developed; that is, a mind that asks questions. Every great scientist has shown this attitude to a marked degree.

2. The Attitude of Intellectual Honesty - This involves the habit of divesting oneself of prejudice, and being honest enough to admit an error when facts indicate that to be the case. It requires that one seek out not only the data that will support one's hypothesis, but that one include all relevant facts and consider them all before drawing a conclusion.

3. Open-Mindedness, An Important Mental Attitude - It means substituting an open and inquiring mind for one that is biased and intolerant. An open mind is one that makes an objective approach rather than a subjective approach to problems. It is receptive to new ideas and arguments. Open-mindedness involves a willingness to consider all possible facts on a matter, even to the extent of searching for opposing evidence. It also involves an unwillingness to accept any answer to a problem as final. Science says, "This is true until further notice," which is another way of saying that all truth is relative.

4. Accuracy in Every Phase of the Investigation - Obviously, habitual inaccuracy would be incompatible with scientific thinking, since all efforts of science are directed toward the discovery of facts. Whenever possible, the scientist attempts to make objective quantitative measurements instead of qualitative judgments, which are of the greatest value in scientific studies.

5. The Habit of Looking for True and Natural Causes for Observed Phenomena, Rather than Accepting Supernatural Explanations - In other words, it is the habit of trying to find the real cause for every happening. This might be called a cause-and-effect attitude. Science assumes natural causes for natural phenomena and seeks in an orderly fashion to discover those real causes.

6. The Habit of Suspended Judgment - This involves the patience to wait until all available facts on a question have been collected, before drawing a conclusion. If the data are inadequate, then the drawing of a conclusion should be deferred.

7. The Habit of Critical Mindedness - This involves a constant lookout for possible flaws in all suggested hypotheses, theories, evidences, conclusions and proposed remedies. This attitude also involves the ability to criticize the thinking of others and especially the willingness to criticize oneself.

8. Review of Findings by Peers - Scientific investigations are written in a concise but complete form and presented before groups of other scientists or published in professional journals as a way of making the study more generally known. This exposes the methods and conclusions of the investigation to other scientists who may find the information useful in their own research, or who might suggest ways in which certain aspects of the study could be improved.

ACTIVITY:

Involving yourself with the same group in which you worked previously, go over the list of scientific attitudes shown above. Examine the actions of your group as a whole, and of its individual members, to see if you can find both positive and negative examples of these attitudes as expressed in your Black Box exercise. Can you suggest other examples that serve to illustrate the importance of these attitudes in science?

Question 12: Are you being intellectually honest when, after doing badly on an exam, you blame everyone but yourself?

Question 13: Why would it not be scientific to speak of truth as absolute?

Question 14: How does quantitative data differ from qualitative?