The Need for Critical Thinking and the Scientific Method

Finlay MacRitchie

• Publisher: CRC Press
• Year: 2018
• ISBN:
  9781351255851
• Edition: 1
• Topic: Politique et relations internationales
• Subtopic: Affaires publiques et administration

The book exposes many of the misunderstandings about the scientific method and its application to critical thinking. It argues for a better understanding of the scientific method and for nurturing critical thinking in the community. This knowledge helps the reader to analyze issues more objectively, and warns about the dangers of bias and propaganda. The principles are illustrated by considering several issues that are currently being debated. These include anthropogenic global warming (often loosely referred to as climate change), dangers to preservation of the Great Barrier Reef, and the expansion of the gluten-free food market and genetic engineering.

oneIntroduction

Part 1: Common misunderstandings of the scientific method

Scientific thinking embodies two main concepts. One is an understanding of the scientific method and the other is what is usually referred to as critical thinking. There is an acute lack of understanding of the scientific method among the population and this is leading to serious deficiencies in the public debate. To illustrate this, we are going to scrutinize just one example of the issues that are currently controversial and which involve science. The example chosen is that of anthropogenic global warming or which is more loosely described as climate change. Immediately, we come up against a problem.

The topic of debate must be defined unambiguously

Most rational people accept that the climate has changed in the past, is currently changing, and will likely continue to change in the future. They also realize that the topic being debated is that of anthropogenic global warming; that is, that there is a significant (measureable) contribution to warming of the planet by human activities. The main human activity is the burning of fossil fuels, which produces what are called “greenhouse gases,” of which carbon dioxide is one. These gases then concentrate in the upper atmosphere and act as a sort of blanket that hinders the escape of heat. The scientific basis of this effect is generally accepted. What is not known with any certainty is the magnitude of the effect. The sloppiness in defining the issue can be a source of confusion. Furthermore, other confusing terms are bandied about such as “carbon pollution” and “putting a price on carbon.”

Other current topics of debate suffer from the same lack of clarity in assigning names. Examples are “same-sex marriage,” which has morphed into “marriage equality,” and another is “multiculturalism,” which can cover a wide range of activities. In some cases, the title of the topic is deliberately manipulated so as to cause obfuscation.

In summary, in order to have a valid scientific debate, it is essential that the topic of debate is unambiguous to ensure that the participants are arguing about exactly the same thing.

A true scientist must be detached

The most crucial change in the evolution of science has been the transition from dogmatic thinking (pseudoscience) to critical thinking (true science). In simple terms, dogmatic thinking involves looking for confirmations of a theory whereas critical thinking is open to observations that do not agree with a given theory. A scientist who uses critical thinking forms opinions, but these are not held rigidly and can be changed or modified by new observations or rational arguments.

What do we find in the debate on anthropogenic global warming? The participants are mostly divided into two groups: those who believe it is occurring and those who do not. This has led to the terms “alarmists” and “deniers.” Placing labels on those who do not agree with your viewpoint is immature and is not in the spirit of true science. True scientists should be detached so as to be able to listen carefully to contrary arguments and be ready to change their opinions. Many of the protagonists in the debate are fierce in asserting their beliefs and casting scorn on their opponents. This is not how an issue should be scientifically debated.

To hold a reasoned scientific debate requires the participants to be sufficiently detached to be open to opposing arguments and to change or, at least, modify their opinion should the argument be logically strong. In cases where the evidence is inconclusive, it is best to defer making a judgment until more light is thrown on the issue.

A scientific theory can never be proven beyond doubt

In the debate about anthropogenic global warming, we hear statements such as “the science has been settled.” Those who make such statements do not understand science. The truth is that the science is never settled, especially for such a complex issue as the one we are considering. The best we can hope for is that research will increase our understanding of the problem and bring us closer to the truth. True scientists retain a certain skepticism so that they always remain open to new perspectives. Dogmatic thinkers close their minds to any ideas that may threaten their established views.

If we examine the approaches being used to throw light on the question of anthropogenic global warming, we see that practically all of the effort has been aimed at trying to find confirmations, either for or against. Have any attempts been made to refute the theory? I am not aware of any. In fact, if only dogmatic thinking is applied to an issue, the idea of trying to falsify one’s strongly held belief is unthinkable.

Separate observations that are consistent with a theory do not correspond to additional confirmation

Many believe that, if an observation is consistent with a theory, then further separate observations that are also consistent, signify additional confirmation. Perhaps an example may help to illustrate what is a subtle point. In the debate on anthropogenic global warming, it has been observed that in some parts of the world glaciers are melting. A further observation is that sea levels in certain parts appear to be rising, a result that would be expected if the temperature were increasing. This then is taken as additional confirmation of the theory that the planet is warming. This assumption has, however, been argued by Karl Popper, one of the great philosophers of science, to be not valid.

What does this additional observation confirm? It simply means that each observation can be interpreted in the light of the theory. If we only look for confirmations, we are bound to find them. If we look for confirmations that the planet is not warming, we can also find them. For example, the polar ice cap in a certain area of Antarctica is increasing in size. The temperature of the earth’s atmosphere has also not been found to have increased over a recent period of about eighteen years, even though the amount of carbon dioxide being emitted from industrial processes has been steadily increasing.

All these observations are important to throw light on the issue and for scientists to form hypotheses. However, they do not necessarily bring us closer to an acceptable theory.

Refutability as a criterion for evaluating a scientific theory

How then, we may ask, is it possible to test a theory so as to give us an answer that can bring us closer to the truth and provides us with more confidence that we are on the right track? Karl Popper wrestled with this problem and came up with a criterion. Instead of searching for confirmations of a theory, we should try to show that it is false. This approach represented the evolution from dogmatic thinking to critical thinking. It opened a way to critically test a theory by trying to refute it. If the experiment succeeds in a refutation, then the theory is discarded and a search for a new theory is commenced. If an experiment to severely test the theory fails to refute it, then we can say that the theory is corroborated for the present but with the proviso that it may be refuted by further experiments in the future.

Consensus is not a criterion for the validity of a theory

Claims are often presented for the validity of a theory by pointing to the number of scientists who support it. The implicit argument is that if 90 percent of scientists support a theory, then this must mean that it is correct. Perhaps 99.9 percent of scientists believe a theory to be true. Therefore, it is inferred that there is an even greater certainty that it must be true. Such logic (or lack thereof) cannot be justified. Many of the great discoveries of science have been made by individuals who have not followed consensus. In fact, it is due to this that they have pioneered new ways of thinking. It is probably a requisite for new advances that they separate themselves from the mainstream.

The illusion of modeling

In recent times, modeling has been developed to try to describe events. It has been spurred on by the advances in the power of computing. The aim in modeling is to input all the variables that are believed to influence a given phenomenon. This then can produce an output that gives an answer to a certain question. For this approach to work requires that all the variables that affect an outcome are fed in and that they are fed in a correct manner. In a way, this approach applies the idea proposed by Popper of devising experiments to refute a theory. If the data are correctly introduced, the result predicted by the theory can be either corroborated or refuted. Providing the problem being tackled is fairly simple, this approach can be successful.

Modeling has been applied to try to describe the effects of human activity on climate. The way that climate changes is a complex problem and the computer programs that have been applied are huge. So far, they have not been able to accurately predict the effects that are being observed. How to interpret this is equivocal. It may be that the theory is not correct so that would amount to a refutation. On the other hand, it may be that the input of information is flawed so that no firm conclusion is justified.

Part 2: General introduction

The way in which individuals form opinions about issues in our society is influenced in two main ways. First, we tend to read books and articles or listen to viewpoints that are in accord with the opinions we have formed from our experiences, thus reinforcing bias. Second, much of the public debate is characterized by distortions of the truth, albeit usually subtle, and, unless alert to this, our thinking may be prejudiced. What is needed to put aside our bias and be able to recognize the lack of truth in what we hear or read? How effectively we deal with this question depends on our capacity for critical thought. Critical thinking is an essential ingredient of the scientific method. This does not mean that we who call ourselves scientists are the only ones who can provide the answers. Scientists are human and suffer from the same failings as nonscientists. We can be gullible, opinionated, and intolerant of the views of those who hold different opinions. What I would like to suggest is that there is a true science and the practitioners of true science are those who strive to uphold its ideals. To do this does not require formal qualifications in science but requires an understanding of what is inherent in the scientific method and how it should be applied. It is therefore an idealized concept perhaps analogous to that of the philosophers portrayed in Plato’s Republic. True scientists are ones who follow the scientific method, which is outlined in Chapter 2. A true scientist brings an unbiased attitude to debate, does not adopt dogmatic viewpoints, is prepared to respect the opinions of those with opposing viewpoints, and is ready to modify his or her opinion if sound counter arguments are put forward.

Sometimes, in this book, reference is made to scientific thinking. This term is meant to embody critical thinking combined with an understanding of the scientific method.

The range of capacity for critical thinking

The capacity for critical thinking is what can determine the contribution that each individual makes to the debate of an issue. We can think of two extremes. There are the critical thinkers who free themselves from the constraints of bias and the distortions of the media. At the opposite extreme, we have those who allow themselves to be indoctrinated and finish up with a narrow dogmatic view of the world. If this simple fact could be recognized by those with an uncritical frame of mind, they would see that they are mere pawns who are exploited and have little control of their destinies. This can be shown by a simple thought experiment. Suppose we have two different cultures in which there is mutual hate and intolerance between them. If we clandestinely take a baby from one culture and exchange it with a baby from the other culture, what will be the likely outcome? The most likely outcome is that each baby will become an adult and adopt the beliefs and hates of the culture into which they have been planted. In other words, they are simply puppets who, although entering the world as humans with all the potential to form high ideals, develop characteristics determined as a result of indoctrination by the society in which they are placed.

Much of the evil that occurs in the world is caused by indoctrination with lies. The puppets who absorb the indoctrination are individuals with little powers of critical thought. Of course, all of us are susceptible to some degree of indoctrination. Perhaps if we could spend more time contemplating such things as a star-studded sky on a clear moonless night far from city lights, witness waves crashing onto a deserted beach, or take in the majesty of giant trees in a forest, this might instill a sense of wonder that could help to break the shackles that bind us to the petty hates and intolerances that tend to envelop us. The main theme in this book is that we can all gain by acquiring greater understanding of the true scientific method and how it can be applied to our thinking.

Distinction between science and pseudoscience

Science involves a search for truth. The philosophy of the scientific method is discussed in detail in Chapter 2. A belief held by many is that science is characterized by its empirical nature; that is, it is based on observations and measurements. To some extent, this is true but it is not the complete picture. For example, astrology is based on observations and measurements of the positions of heavenly bodies but is not regarded as a science but more as a pseudoscience. The distinction between science and nonscience or pseudoscience is elaborated in Chapter 2. Put in its most simple form, it is that a valid scientific hypothesis is testable and therefore, in principle, refutable, whereas a nonscientific hypothesis is not. We may briefly illustrate this by considering the issue previously mentioned to use as an example, that of anthropogenic global warming. It is doubtful if any rational person would not agree that the earth’s climate may be changing, has been changing in the past, and likely will continue to change in the future. Of course, nearly everyone understands that the current debate is about whether there is a significant anthropogenic (caused by humans) contribution to warming of the planet and that the effect is due to emission of greenhouse gases, of which carbon dioxide is o...