Can Critical Thinking Be Taught?


Can critical thinking be taught?[1] From the perspective of science and scholarship this is an extremely important question; nor is it less important from the viewpoint of education and instruction.

From the perspective of science and scholarship the answer to it matters greatly because the organized search for knowledge and understanding is impossible without critical thinking. If the theories, methods and procedures of science were not subjected to constant criticism, science would stagnate and soon cease to exist. Progress in science depends upon people doubting prevailing theories, trying to find their points of weakness. In fact, this seems to be the main precondition for progress in any field: critically examining the standard way of doing things and trying to find a better one; looking for the flaws in any human endeavor—whatever it may be—in order to be able to do better.

From the perspective of instruction and education the answer to our question is also of the highest importance, since one of the main objectives of instruction is precisely making the students better able to deal well and productively with various subjects and challenges. Nowadays hardly anyone would call into question that one of the main aims of education is to make the students independent and capable of solving problems on their own. However, this aim is quite unrealistic unless one presupposes that the students will be taught to think critically. Is it, then, certain that critical thinking can be taught? Now, some of my listeners may only be interested in my conclusion rather than in the reflections and speculations leading up to it, i.e. the various considerations behind my specific answer, affirmative or negative as it may be. It is, of course, quite understandable to have a limited interest in such reflections—in daily life we are rarely interested in questions as such, though we are interested in the answers to them. We constantly need to learn some fact or another, and often it matters little how we get our information—what matters is that we do get it. In the same way, we are often interested in other people’s views, although we have little or no interest in the reasons for these views, in why they believe or think as they do.

The truth is that in daily life we are rather uninterested in thinking critically. While we do want to obtain facts, information and opinions, we are less interested in what renders a fact truly certain, our information reliable or the opinions insightful and possibly correct. This disinterest in reasons and grounds has many causes, some of which I will discuss later. Perhaps the art of teaching critical thinking consists precisely in overcoming this disinterest. Once I asked a secondary school student whether he thought that he would be able to learn to think critically. After thinking for a short while, he answered in the affirmative; when I asked him why he thought so, he said quite simply: “Anything can be learned.” I thought this was quite a good answer, so I asked further: “Can critical thinking be taught, then?” This time he thought for a bit longer, but finally answered: “Yes, no doubt it can be taught…”—here he paused, and then added: “… if you can find anybody who is interested in learning it.” Then he addressed a question to me in return: “Isn’t it possible for people to get on just as well in life, even if they don’t worry about the reasons and grounds behind various views?”

The first question we should consider, then, is the following: Why should we scrutinize our ideas, our beliefs, and our grounds for holding them? The best way to realize the importance of doing this is perhaps to consider their role in our lives. Ideas and beliefs have the very practical role of helping us to organize our lives, clarify our intentions and implement our plans. Critical thinking enters into this as an instrument for refining and reshaping the tools which above all others are needed in the struggle of life, namely ideas and beliefs regarding everything under the sun. Without them, people would be in immediate contact with their physical circumstances, being forced to react to them without having any control over their responses. They would then, like the animals, be totally dependent upon their environment.

The practical value of ideas and beliefs is in fact so obvious that there is little reason to expand upon the point. Nevertheless, it seems that many people do not realize this and completely fail to attend to their own beliefs and ideas, as if the latter could independently sustain themselves, needing no nurturing. Unfortunately, few things are further from the truth. Ideas are among the most delicate creatures in this world; they can only thrive and prosper in a person who cares well for them. Thinking is impossible without ideas and beliefs. They are, at one and the same time, the materials and the tools of the mind. They enable us to understand the things around us, so that we can in turn change them, enjoy them, or turn them in one way or another to our advantage. That is why we should take good care of our ideas and beliefs, using any opportunity for clarifying and sharpening them, and above all making sure that ill-considered views do not guide our decisions and actions.

I have now given one general argument, based on utility, for the conclusion that critical thinking should be taught. However, this argument of course by no means guarantees that it can be taught. No need, however strong, carries with it a guarantee that it can be fulfilled. Unfulfilled needs are what we lack least of all! We therefore need a better argument if we wish to maintain that critical thinking can be taught. This argument is in short this: It is wrong to believe anything on insufficient grounds. Here we seem to have a particular rule or principle which, when applied, may discipline people into thinking in a more critical manner.

This simple statement is the essence of the rationalism which has ensured the progress of science and education in the West—a progress which has been gained only through a hard struggle against all manner of superstitions and irrational beliefs. This struggle, however, is far from over. In most, if not all, areas of daily life, public discourse is dominated by prejudices, pre-conceived notions and over-hasty judgments—in other words, putting it a bit more politely, by “unsupported assertions”.

There is, therefore, every reason to attend closely to the proposition which is here being put forward as a principle: that it is wrong to believe anything on insufficient grounds. Some people might impetuously object to this, demanding that I immediately produce a supporting argument. Why should it be wrong to believe whatever one wishes? Don’t we have the freedom to believe anything we like? How can one justify these kinds of restrictions upon our beliefs and opinions? Freedom of religion, freedom of thought—are these not the most basic of human rights? And why put such a great emphasis upon having reasons and grounds for all our views? Such questions are, however, profoundly beside they point. They are far removed from anything which matters in connection with the simple principle that it is wrong to believe anything on insufficient grounds. In fact, they are examples of the very hastiness which causes people to lose sight of what is important, always failing to understand what is being said in their haste to affirm or deny. Let us therefore consider the matter carefully before we render judgment on the value of the aforementioned principle.



The assertion that it is wrong to believe anything on insufficient grounds constitutes a commandment of critical thinking. It is now time to ask: What is critical thinking? Critical thinking is the kind of thinking which does not assent to any view or statement without having first examined what it involves and found sufficient grounds for it. In other words, critical thinking is a process of searching for new and better reasons for one’s ideas and views, and consequently of continually revising them.

This critical principle is the foundation and regulating principle of any proper field of inquiry. It sustains the questions which are the essence of all systematic inquiry: Which reasons are significant? What kinds of grounds are valid?

It seems, therefore, that it is not merely a matter of critical thinking being extremely positively regarded by those who apply themselves to science and scholarship or to the strengthening of knowledge and education. Rather, it is the very foundation of their endeavor. It is therefore interesting that the words “critical” and “criticism” in daily speech normally refer to censure and negative judgments. Who is not familiar with the expression, “Oh, don’t be so critical”? In fact, using this expression is often fully justified. What passes for criticism is in many cases merely quibbling and general negativity.

There are, however, other and more important reasons for considering criticism to be something negative. In the first place, the reasons people have for their beliefs, ideas and theories are often not easily at hand, which makes it all too easy to point out that they believe something or take it to be true on entirely insufficient grounds, for instance that “it said so in the newspaper” or “Daddy said so” or “the teacher said so”. Not that I am maintaining that there is always reason to doubt what is printed in the paper or what is said by one’s parents or teachers; I am merely pointing out that as a rule it is a rather feeble reason for believing something that somebody else said that it was true. Granted, we often have to rely upon the opinions of others—parents, teachers, specialists and so on—but we must never trust them blindly. As soon as we have reached a certain maturity we should ask for supporting arguments.

Another reason that the word “criticism” has acquired some negative connotations in daily speech is that it is heavily used in connection with the evaluation of works of literature and art, which is an area where fashion and the variability of human taste have a great importance. It so happens that it is much easier to point to whatever is detrimental to the quality of a work than to what gives it value. What gives a work value—makes it into a good work of literature or art—is generally a very complex interplay of innumerable factors which it is extremely difficult, even impossible, to describe in any detail. In order to grasp it, you simply have to read the text or see the work of art. What detracts from its value, on the other hand, is by and large some particular set of features which stand out, unmistakably bearing witness to the incompetence or clumsiness of the artist; and such specific flaws are generally easy to describe to people.

The same applies to people’s ideas and views in general. It is much easier to demonstrate that some particular supposition is false than to point out the correct one. This is clearly seen in science and other forms of inquiry, whose main characteristic is a constant striving to revise the grounds of theories and methods, looking for weaknesses or flaws in procedures and presentation. Considered superficially, such criticism may seem purely negative, but in fact it is the main precondition for success in any branch of study. Wherever people are striving for perfection, criticism is justified and necessary. Without it we would be unable to realize what needs fixing or what impedes progress.

That much is obvious. However, as yet we have not shown that the principle of critical thinking is correct, i.e. that it is valid for all people and all circumstances. I have only pointed to its value in fields where there is a drive for success, for betterment, for perfection. Nor have I, as yet, said anything about how one might teach this principle: that nothing should be held to be true without due inquiry or without knowing the reasons. Even if one is fully familiar with the principle which prohibits believing anything on insufficient grounds, it does not automatically follow that one will endeavour to follow it in any systematic manner. For comparison, take the belief in God. There are, after all, quite many people who claim to believe in God, and no doubt do believe in a purely verbal sense, even though one would be hard-pressed to see any signs of it in their behaviour.

Similarly, such behaviour as constantly invoking the principle of criticism, frequently taking exception to the opinions of others or demanding reasons and supporting arguments, does not guarantee that one is practicing critical thinking. The tendency to object to the views or actions of others, or even of oneself, has by and of itself nothing to do with critical thinking. Rather, critical thinking primarily consists in making an effort to inquire into things, and in refusing to let any inclinations, desires or emotions mislead one. Teaching people to think critically is far from a simple matter. By itself, it is obviously not enough to teach people particular procedures for looking into things on their own. It is also necessary to get them to adopt the will to believe nothing other than what is grounded in inquiry, instead of letting their thoughts be controlled by their own wishes or concerns. For that is what is meant by the principle that it is wrong to believe anything on insufficient grounds. The principle must be imprinted upon the minds of people; it needs to be their natural way of thinking if it is to be effective and successful. People must have learnt and understood that this principle has a universal value, that it applies anywhere, to anyone. Otherwise any talk of people having learnt critical thinking will be idle.

But can we really claim that the principle of critical thinking is so universal in its scope that it applies to any situation and for any person? Is it not possible that it applies only in areas where people are striving for progress and perfection, such as in science and other forms of inquiry? With what right and on which grounds can we assert that the principle is correct, has value for everyone and in all circumstances, and that it therefore can be taught?



Many have attempted to answer these questions. Among them is the British mathematician William Clifford (1845–1879), whose essay, “Ethics of Belief”, argues that the principle of critical thinking is universal.[2] In Clifford’s own words: “it is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence”. Even if the Icelandic translation of this article has not, at the time of speaking, appeared in print, it so happens that a rejoinder to Clifford’s thesis has been published in Icelandic. This is an essay by the American psychologist and philosopher William James, entitled “The Will to Belief”.[3]

This is not the place for a detailed treatment of the arguments given by either Clifford or James. However, I will mention some main points which are directly relevant to my subject matter in this lecture. Clifford’s arguments for the thesis that it is a universally valid precept that one should never believe anything on insufficient grounds, are in broad outline as follows:

The question of right and wrong always applies to the grounds of an opinion or belief, not to its content. What matters is how people form an opinion, rather than what the opinion is or what it is about. From the vantage point of critical thinking, therefore, it does not matter what we believe or what our opinions are, but only how we have acquired our opinions or gained our belief. Let us say that we believe that a teacher is abusing his or her authority over the students and is trying to get them to believe in some piece of superstition. However convinced we may be of this, we have no right to that conviction until an inquiry has been made into the matter. In the judicial system, this rule is a commonplace. No one may be considered guilty until guilt has been proven. This is Clifford’s first argument, and it amounts to nothing more than pointing to a simple and obvious fact which, unfortunately, people often overlook. In their involvement and fascination with the subject-matter of their views, they forget to attend to how they acquired their beliefs and what grounds they have for holding them.

A second point is the fact that any real conviction influences the actions of those who have it. Our views constantly give rise to decisions, actions and various kinds of behaviour. In fact, it is completely impossible to draw a sharp distinction between judgments about people’s views and about their behaviour. As soon as we render judgment on someone’s actions we also judge his or her views and vice versa. Even if some particular conviction does not immediately lead to action, it may do so at any time. Clifford also points out that any conviction or action enters into a very complex web of ideas and beliefs. One mistaken belief about a minor matter may in effect spread its poison, thus greatly weakening that web of belief which at every moment of our lives links together the external influences on us, on the one hand, and our actions, on the other.

A third point is this: There is no such thing as a private conviction, a belief which concerns no one else. According to Clifford, “Our words, our phrases, our forms and processes and modes of thought, are common property, fashioned and perfected from age to age; an heirloom which every succeeding generation inherits as a precious deposit and a sacred trust to be handled on to the next one, not unchanged but enlarged and purified…” Thus it is—strictly speaking—a crime to adhere to, and take decisions in accordance with, beliefs which we have not previously investigated with regard to their tenability. It is this last argument which, according to Clifford, is by far the most important, and it is the one which he treats of at the greatest length. The crux of it is that by being credulous and forming our beliefs on the basis of insufficient arguments, we are wronging everyone else and are moreover weakening our own means of self-mastery. In other words, we become dependent and corrupt at the same time.

We must let this suffice with regard to Clifford’s arguments. Before we take our leave of him, however, there are two possible objections that we should consider for a moment. Clifford himself alludes to one of them. “But,” someone may say, “I am a busy man; I have no time for the long course of study which would be necessary to make me in any degree a competent judge of certain questions, or even able to understand the nature of the arguments.” To such a man, Clifford simply retorts: “Then he should have no time to believe”. In other words, we should be neutral with regard to those matters of which we are not competent to judge; we should not take up a position or form an opinion until we have acquainted ourselves with the subject.

This rejoinder certainly seems quite sensible. But—and here we have an objection with which many people doubtless will agree—unfortunately this is impossible in practice. We are repeatedly bound to form an opinion or take a decision without having the time to attend to the appropriate reasons or grounds, that is to say, without having had the opportunity to investigate matters as well as we should.

Before replying to this, I also want to mention another, even more definite objection to Clifford’s thesis. In many matters, for instance in religion and politics, it does not even seem possible to find decisive arguments supporting or refuting one position more than others. Nevertheless, it seems quite impractical to abstain from forming an opinion or taking up a position in these matters.

This latter objection is the core of what William James has to say on the matter. His view is that in many areas, not least in religion, we should base our stance upon feeling, choosing the position which most appeals to us, even if we have no pertinent arguments in support of it or a reason to believe it beyond our wishing that it is true. This may seem wise to many people. A very similar attitude is found in Sigurður Nordal’s lectures on Life and Death,[4] which I am sure that many of my listeners have read and are familiar with.

However, I consider that both of these objections have cogent answers showing that they do not affect the thesis that it is wrong to believe anything on insufficient grounds; nor do they apply to the arguments by Clifford which I recapitulated above.

The first objection was that it is impossible to live by the principle of critical thinking because we continually have to form beliefs and take decisions without having the opportunity to get sufficient grounds for them. The person making this objection seems to take the demand which the principle of critical thinking makes upon us too literally. It goes without saying that when there is no time to consider matters, for instance when there has been an accident, the principle does not tell us to abstain from forming a belief or to do nothing. We are bound to make up our minds in an instant and do whatever we think is best at the time. If we have cultivated the habit of appraising things in the spirit of critical thinking it is likely that our reaction will be appropriate, that we, almost without conscious thought, form a correct view of the situation and of the proper course of action. The view that people who make a practice of critical thinking find it harder to reach a decision than those who are accustomed to act before thinking is nothing but the prejudice of someone who has not gone to the trouble of scrutinizing the matter.

The second objection, the one I attributed to William James, is a more weighty one. It states that there are certain subject-areas which are of such a nature that it is impossible to reach a final conclusion regarding them. Even so, it seems irrational, even flat-out wrong, not to form a belief, to take a stance, to give one’s adherence to the view which most appeals to one. Clifford would, however, reject this, saying that we should be neutral in those matters where there is no possibility of a definite conclusion. But in this instance, Clifford’s attitude seems impractical, and in fact he himself had some definite religious views even if he can hardly have had access to better evidence in that area than anyone else. William James, therefore, seems to have a strong case in this regard. There really do seem to be weighty reasons for supposing that in many important matters, especially in religion, morals and politics, the feelings, desires or interests of people must be the foundations of their beliefs, actions and decisions.

In my opinion, there is here a real danger of committing a serious fallacy which all-too-seldom is remarked upon. It is of course true that in many instances beliefs, decisions and actions are determined by emotions, desires, self-interest or indoctrination of one kind or another, not least in matters of religion, politics and morals. We are well aware of this—and here comes the erroneous inference—therefore we think that logical reasoning and critical thinking cannot be brought to bear on these matters. However, the truth of the matter is that, given the fact that our views are in some areas frequently decided by reasons which have little or nothing to do with logical argument, we should on the contrary conclude that it is precisely in these areas where critical thinking is the most sorely needed and, moreover, most likely to do some good. This becomes obvious as soon as one gives the matter some thought. In scientific and scholarly inquiry the demand for critical thinking is the greatest precisely in those areas where there is the greatest and most serious controversy. Why should not the same principle apply to religion and politics, where the self-interestedness and emotions of people have the most effect upon their thinking? Of course, it is here that critical thinking is truly put to the test, which obviously means that there is the greatest risk that it could fail. But it is absurd to maintain that it cannot be applied or that it is inappropriate in such matters. In fact, I do not believe that William James held this view; he seems simply not to have fully realized what conclusions could be drawn from his defence of the rights of the emotions. Now, certainly emotions are not only appropriate but even necessary for people to be able to focus on some important matters. However, an emotion which completely overpowers reason is of course not a healthy one, nor would reason be healthy if it were to disregard the value of emotion. In the end, it is nothing but a clear and logically supported emotion which enables us to see that the principle of critical thinking applies everywhere and to any thinking person. In a great many areas the conclusions depend precisely upon well-founded emotions which we are quite able to explain and support by argument.



It may now appear that we have reached a positive answer to the question whether critical thinking can be taught. It should be possible, given that we are able to find or form appropriate teaching materials and methods for impressing upon our students the maxim of not believing anything on insufficient grounds. It may therefore seem to be time to abandon the question “Can critical thinking be taught?” for the further question “How may critical thinking be taught?” In this case, we should have to find appropriate methods and material for training students in applying the principle of critical thinking and drilling them so that they cultivate the habit of following this principle to the greatest possible extent.

There are, however, two doubts which may be raised and which have to be examined further. In the first place, some may—despite what was said above—consider the task of teaching critical thinking to be a completely impractical one, since people are in their very nature such that they are not led by argument but by other reasons, however useful or necessary it may be to learn to think critically. This objection must be taken very seriously, for it is quite true that it would not be difficult to point to examples of people who are well-informed and who apparently have acquired the habit of critical thinking, but who nevertheless, when push comes to shove, base their attitudes upon something other than logical reasoning. This raises a deep concern about the efficacy of critical thinking. Is it possible that, when it comes right down to it, reason is powerless, that independent, critical thought is, in the last analysis, merely an illusion? Is it not then also completely idle to speak of teaching rational thinking?

That was the first objection. The second is of a similar kind and takes its point of departure in everyday experience. It often happens that people are quite critical in areas in which they have some special competence but are quite devoid of the critical attitude in other matters. This raises the following question: Might it be the case that it is only possible to train people in critical thinking in particular areas, for instance in logic or economics, while it is impossible to teach them to think critically in general? One might then go on to ask: Is it not unnecessary and even misleading to speak of teaching critical thinking? Is it not rather a matter of acquiring knowledge and competence in some specific field? It would then be a further, unrelated matter whether such knowledge or competence enables people to think critically about other things, or about life and the human condition in general.

The first objection is more general and goes deeper, but the second one is nevertheless just as important, especially with regard to the question of how any teaching and training in critical thinking should be organized. If I succeed in refuting these two objections, then I will consider myself to be able to give an affirmative answer to the question, “Can critical thinking be taught?” In that case we could embark upon the second phase of our inquiry, namely looking for answers to the question “How should critical thinking be taught?” I hope that I will later have an opportunity to address that question.

We should be careful not to be swayed by prejudice. “Of course, we can acquire the habit of critical thinking,” a listener may be thinking, “for we have many examples of people who have acquired it, which shows beyond any doubt that it is possible.” And this imagined listener might add: “Are you not yourself among those who have learned to think critically? Must we not assume that you are, since you consider yourself qualified to appear on the radio, discussing critical thinking?” Now, it is one thing to know a thing or two about critical thinking and quite another to possess the ability oneself. Besides, I personally do not know enough about the nature and limits of critical thinking, which is precisely why I am looking into it. At this stage, in fact, I myself am full of doubts, even allowing myself to ask: Is it not possible that the very idea of critical thinking is merely an illusion, a mirage?

And one might imagine a different listener thinking at this very moment: “Is not all this talk about critical thinking so much hot air?” Such a person might continue: “It is all very well and good that someone wants to go to the trouble of speculating about this, but it is quite clear from the outset that it is a hopeless task. We are, after all, so constituted that we believe whatever best fits our own self-interest, and merely call those things reasons or grounds which we use to convince ourselves and others of what we find convenient to believe at any given time.”

Is it possible that these assertions are correct? However much we may oppose them, they cannot be dismissed solely on the grounds that they are prejudices. Of course, it is not laudable to take up a prejudice, but the same applies to them as to other judgments: whether they are supported by argument or not, they must be either right or wrong. We cannot, therefore, take it as given that we are in complete control of our own thoughts, beliefs and ideas. On the contrary: there are examples of people who believe, decide and act without attending either to logical reasoning or to the real reasons for their beliefs, acts or decisions. In fact, most of us probably belong to this group.



Now, to some people it may be an uncomfortable notion that we do not have control over our own ideas and decisions. But what reasons could we have for supposing that we have the ability to think independently and to form our own beliefs? Or—to put the question differently—why are our thoughts not being directed by logical reasoning or by reasons which we ourselves have evaluated using our own judgment?

This is something I alluded to previously, when I recapitulated William James’ objections to the thesis that the principle of critical thinking was a universal one. His view is that in certain matters, our beliefs must depend upon emotions, self-interest, wishes and desires. James is here primarily thinking of people’s moral and religious attitudes. My answer to this argument was that the fact that our beliefs are frequently determined by emotion or self-interest does not absolve us of the duty to apply critical thinking. On the contrary, it is precisely in those areas where self-interest and emotion have the strongest influence that the need for logical reasoning is the greatest, so as to prevent our attitudes from being determined by blind and involuntary forces. And probably James would have agreed in this, even if he would not have put it in the same terms. The question, then, has now become whether this is really possible, whether we are not simply so constituted by nature that various non-rational forces determine our thoughts and actions: innate dispositions, impulses, desires, self-interest or feelings over which we have no control. For such would be the involuntary forces truly determining our thoughts.

This hypothesis is at once simple and radical. And such hypotheses require one to take special care if they are not to lead one into trouble. Their simple and radical character may deceive one by restricting one’s perspective on the issue. William James, for instance, would not consider such an hypothesis to be a sensible one. He might even dismiss it on the grounds that it is much too one-sided and inflexible. Let us therefore begin by taking a look at his attitude in this matter. James is ready to agree that in certain areas emotions, rather than reason, should decide. However, the emphasis here is upon the words “in certain areas”, by which he means such matters as reason is not fully able to grasp. In other words, when no decisive argument can be given, we must yield to the rights of the emotions. There is a certain view of human nature which seems to underlie James’ view (although he does not discuss this). On the one hand there is rational man, having the ability to render judgment and reach a reasoned conclusion. On the other, there is man the creature of emotion, who reacts to circumstances in an illogical manner.

On the basis of this distinction, one may reject the hypothesis that external forces determine all our thoughts. There would then be no need to suppose that our emotions are clouding our judgment in areas where cold reason holds all the cards, for instance in logic or mathematics. Now, this idea of the double nature of man is an ancient one, and William James is in good company with his theory, since both Plato and Aristotle had their own versions of it. Besides, this theory is in good agreement with the general attitude of people to themselves and to others. Most people are accustomed to regarding reason as the logical part of the soul and the emotions as the illogical part. James, in fact, accuses those who want to generalize the principle of critical thinking (the demand for sufficient grounds) of not recognizing the fact of this distinction. According to him, they intend to let reason, with critical thinking as a guide, overpower all emotion, if not extinguish it. In fact, James considers such people—and here he is thinking of Clifford, whom I discussed previously—to be Janus-faced, in that their defense of critical thinking is an emotional matter even as they pretend only to accept logical argument and sufficient grounds.

Now, I agree with James that this is an emotional matter, but I am not certain that it is a mark of hypocrisy or inconsistency. As for myself, I am ready to defend the view that this idea about the double nature of man does not hold water. Human reason and human emotions are not, in my view, two separate things; they are, in the last analysis, a unity. Reason may be more or less emotional; similarly, emotions may be more or less rational. My arguments for this view are quite simple. In the first place there is no more reason to say that emotions are illogical than that reason is illogical. The fact is that emotions may be logical and illogical just as judgments may be. Secondly, emotions may be more or less rational depending on the reasons for them. Common emotions such as anxiety, anger, love, may be rational or irrational according to the circumstances. My conclusion is therefore that emotions are a part of reason and that reason is a part of the emotional side of life. Reason and emotion are not two clearly separate faculties of the soul, but two opposites or poles of one and the same faculty. It was on the basis of this that I said earlier in the lecture that it was a clear and logically supported feeling which told us that the principle of critical thinking was valid for anyone and applied to any subject-matter.

But if it is the case that emotions are not essentially distinct from reason, then it seems natural to conclude that they direct our thoughts to a much greater extent than rationalists such as Clifford would care to admit. And if so, there seems ample reason to doubt that independent critical thought really exists.



Let us now suppose that the reasons for our thoughts—including our beliefs and decisions—are usually not logical arguments but emotions or forces over which we have little or no say. It would then be simplest to assume that, aside from emotions, these forces comprise desires, impulses, self-interest and personal character. But this would of course not be sufficient, since people also have all kinds of beliefs which may be traced to indoctrination, upbringing or the spirit of the times, but which they may never have consciously considered whether they wish to hold. The clearest indication of this is the fact that people may believe various things which go directly counter to their self-interest and their desires. It therefore seems to be appropriate to divide the main reasons behind our thoughts into two kinds: on the one hand wishes, impulses, self-interestedness and character, and on the other indoctrination, upbringing, spirit of the times and authority. These two kinds may coincide, i.e. when what is impressed upon one is in accordance with one’s wishes, such as when a patient is reassured that he or she is on the road to recovery. Note that the patient may be recuperating quite independently of whether he or she is informed of it, or indeed wishes to get better at all. These reasons for the belief—the inculcation or the wish—are irrelevant to its truth-value. (Sometimes wishing makes things so, and the old saying “faith can move mountains” is far from being absurd; but this nevertheless does not change the general truth that neither hope nor faith determine whether our views are true or justified; even if we hope and trust that something in particular will happen, and have weighty reasons for believing and hoping, we do not know whether it will in fact happen.)

From this it may be seen that there is a great difference between, on the one hand, such reasons of which I have just given some examples and, on the other, the grounds of our beliefs, understood as those factors which determine whether they are true or false. This distinction is obviously an important one. Nor should it necessarily affect our assessment of the justification or truth of an opinion whether an explanation can be given for how it happens that somebody holds or maintains it. One’s beliefs and opinions may be true whether or not one derives them from secure foundations, and whether or not they spring from self-interest or irrational desires. This is something we frequently overlook, considering the opinions of others invalidated, even beneath notice, if they clearly and obviously are determined by self-interestedness or prejudice.

In everyday discourse we do, in fact, often think in this manner, judging the beliefs of others, or rather their expressed views, based on the opinions we ourselves hold of their persons, their motives or their self-interest. We consider their beliefs to be determined by their character, education, line of work or gender, and evaluate their views in light of who puts them forth: a man or a woman, a child or an elderly person, a farmer or a fisherman, a chairman or a charwoman. However, this sometimes leads us into a serious fallacy, which happens at the point when we go so far as to completely disregard whether the views of these others are right or wrong, on the assumption that they are determined by forces over which people have no control and may not even be aware of. In doing so, we not only violate the principle of critical thinking by not considering the grounds for beliefs, as it requires us to do, but we renounce its basic presupposition, in that we are implicitly denying that people are free to choose their own views.

Let us note that exactly those features which we take to invalidate the views of others may constitute excellent grounds for holding them. This especially goes for emotions, since they may at the same time unconsciously direct one’s thinking and provide a reason for thinking that one’s views are correct. It is therefore plain that it is always unreasonable not to consider whether an opinion is true or false on its own merits, whatever may be causing people to hold it; not only would it be arrogant to disregard this, but foolish as well. Moreover people’s motives often shed some light on their beliefs, even when they do not constitute grounds for them. Everyone possesses a particular store of experience which enables that person to see more clearly and penetratingly than others in some matters, regardless of whether or not he or she can provide logical arguments in support of that insight. Often the arguments emerge after the fact, after we already have formed our opinion and taken a stand as to what we think is the case.

It is also well to remember, especially if one has a fondness for clear and incisive arguments, that logical reasoning is often misused for the purpose of justifying a position or a view which is in fact quite groundless. It would be easy to point to innumerable examples of this from daily life, where people often seek to persuade others with false or misleading arguments or use them to cover up the true grounds of their views, decisions or actions.



What conclusions, then, should we draw from our extended consideration of the hypothesis that the thoughts, decisions and actions of people are determined by forces which, by and large, are irrelevant to the justification or truth-value of their views? There are three points I wish to mention here. In the first place we should accept that this is correct: our views really are determined, to a great degree, by forces over which we have no control. But, again, this is irrelevant to the question of whether we should consider them right or wrong. The widespread tendency to evaluate views based on who maintains them and from what motives, ignoring the further question of whether they are true or false, is nothing but a bad habit which absolutely must be broken—a bad habit which goes against the principle of critical thinking. The principle, however, remains just as valid, regardless of whether people’s views are determined by reasons other than truth and falsity.

In the second place—and this is the most important point—every one of us already knows what has been said in the foregoing, although some of us may not have thought very much about it. We know that there are all kinds of motives deriving from self-interest, wishes, authority, prejudice and God knows what else, all of which affect what we think and how we think. And we know that people frequently abuse logical reasoning as a means of concealing the true reasons for their actions, in order to justify themselves or to excuse their behaviour, as the case may be. The fact that we know this, about ourselves as well as others, changes everything. We can be independent in our thinking because we know that not all our ideas and views have a solid foundation, and some of them, perhaps, no proper foundation at all. What this knowledge tells us is simply not to trust any belief completely or without reservation. It is always possible that it is not true, and that the grounds we have for it will turn out not to be reliable. This does not imply that we have good reason to doubt all our beliefs and to believe nothing, but that we should be open to possible doubts and ready to take up new supporting arguments or to change our views, if and when the occasion arises. That is all that critical thinking requires of us.

Thirdly and finally, it is easy to see that the very act of doubting whether people are constitutionally unable to make a habit of critical thinking will in and of itself help us to understand the nature and limits of critical thinking. We are not purely rational creatures gliding dispassionately through the world, observing everything through the lens of critical thinking, with all the reasons and arguments solidly in place. We are human beings of flesh and blood, with complex emotions, all kinds of concerns, desires and wishes, but despite everything possessed of the ability to search for truth and justice.



It is now time to turn to the second doubt which I mentioned previously, according to which it is by no means a given that people will generally become more critical in their thinking even if they have been taught to think critically in certain matters or in a certain field. To take a concrete example, the truth is that a rigorous study of logic is no guarantee that one will make a habit of critical thinking in all the matters on which one forms an opinion. It may be conceded that studying logic increases the probability that one will become critical in one’s thinking, which is exactly why logic has long been thought to be a necessary part of a general education. However, it is far from being the case that studying logic suffices to make one logical with regard to every subject. Nor is this specific to logic, since the same applies to any of the several other fields of study that clearly involve some training in critical thinking.

How are we to explain this peculiar fact: that people who are critical in one area become quite uncritical when it comes to other matters? Now, an obvious answer is that people may claim that they have no knowledge of some areas, and so critical thinking would be useless; accordingly, they simply choose to accept what others say, especially if they are specialists or researchers in the field in question. This is all well and good, as far as it goes; in today’s “expert society” one can certainly understand such an attitude. However, the issue is a larger one. For often we consider ourselves to know much more than we have any grounds for claiming, and we do not hesitate to render judgment on and pronounce upon subjects of which we have no knowledge. In short, we are surprisingly uncritical—even in the name of critical thinking.

Human weakness comes to mind as an explanation. However, weakness in such cases is nothing but lack of judgment, which in turn is the same as lack of critical thinking—so the answer still eludes us.

Our problem is this: In some matters we form our views based on the methods of critical thinking. In other matters we form our views while ignoring critical thinking. In order to solve this problem we must account for the various non-critical ways in which people form their views. Thereafter we must clarify how these ways relate to the way of critical thinking. It is impossible to give a comprehensive account of this in the time available, so I will merely summarize a few main points, relying especially on the work of the American philosopher Charles Sanders Pierce (1839–1914) as he formulates it in the article “The Fixation of Belief”.[5]

In his article, Pierce distinguishes between three different ways of forming a belief, aside from the one which I have already mentioned, i.e. critical thinking, which Pierce in fact calls the way of scientific method. These other three ways we may loosely call the way of tenacity, the way of authority and the way of prejudice.[6] I will now describe each of these ways and mention their main advantages and disadvantages.

The first is the way of tenacity. It consists in forming one’s views by choosing to believe tenaciously whatever one likes the best in the beginning. The method consists in repeating constantly to oneself that the view is a right one and to direct the mind to those facts that support it, while at the same time learning to despise anything which might shake that belief. Many people are in the habit of following this simple and direct method. They are careful, for instance, to confine themselves to reading only certain newspapers and magazines, avoiding anything which might cause them to doubt their own views. Pierce tells an anecdote about a friend who advised him not to read a certain newspaper lest it might change his views with regard to free-trade. “Lest I might be entrapped by its fallacies and misstatements,” was the form of expression. “You are not,” my friend said, “a special student of political economy. You might, therefore, easily be deceived by fallacious arguments upon the subject. You might, then, if you read this paper, be led to believe in protection. But you admit that free-trade is the true doctrine; and you do not wish to believe what is not true.”

The way of tenacity, then, consists in holding fast to one’s belief once it has been formed, letting nothing shake one’s faith. This method obviously has some advantages, especially for those who are indecisive and find it hard to make up their minds. It provides calmness and peace of mind. If it is employed systematically, it becomes more likely that one acquires firmness of character and is ready to follow through on one’s decisions to the very end. The main drawback, on the other hand, is the fact that it is impractical and makes it more difficult for one to get along with others. When those who employ it stop to think for a moment, they realize that other views have their place, too, after which they are prone to uncertainty and insecurity. People are constantly influencing the beliefs of one another, so the problem then becomes how these beliefs form, not in the individual but in the society.

Here is where the way of authority enters into the picture. Let the state or some other institution decide what to believe and which views are the correct ones, repeat them constantly, teach them to the young; and also make sure that it has enough power to make sure that alternative views cannot emerge and flourish. About this method there is much to say, much more than we will be able to in this context. It is by far the most efficient way ever invented to form and fix beliefs. Simply hand over to the State, the Party, the Church, the task of deciding what to believe, what one’s views in life should be. According to Pierce, this method will always have the greatest influence on the views of the masses. Those who hold power in society will always think that dangerous ideas must be suppressed. If the state fails to do it, other strong forces in society will take into their own hands the defence of “right views”. In this context, Pierce speaks of a “moral terrorism”. Interestingly, however, the persecutions do not necessarily come from the outside. People often suffer and fall into depression because they feel that they have started to believe something which they have been indoctrinated to consider contrary to all morality. Peaceful and easy-going people find it difficult to resist the temptation to confer on some authority the task of deciding their views for them.

As for the advantages and disadvantages of the way of authority, we may be quite brief. The main advantage is that it ensures peace and social cohesion. The disadvantages lie in the direct or indirect persecutions which the opponents of the prevalent view must endure. It should be pointed out, however, that how this way is carried out differs widely among different societies, depending on their political organization and moral values. And we should remember that no institution, however powerful, can decide upon how the public should think, except with regard to a very few important issues. In most matters, each individual must form his or her own views. Enter the way of prejudice.

This method consists in forming one’s beliefs in accordance with what one finds most natural; or rather, to form any new opinion so that it fits as well as possible into the views which one already has. This seems to be a very natural method, and above all a very convenient one. Some of the clearest examples of it may be drawn from the history of philosophy, where people have organized their views into definite systems, to which they then make any new beliefs conform. Sometimes deep differences of opinion may make themselves felt, however, in which case it is important to have a sufficiently general theory which people can understand and apply to the situation in question. As an example, Pierce mentions the well-known theory according to which everyone acts selfishly, i.e. on the assumption that the chosen action will afford one greater pleasure than the alternatives. Many people consider this to be the only reasonable theory about human behaviour, even if, according to Pierce, it “rests on no fact in the world”.

To be sure, the way of prejudice makes up for some of the disadvantages of the ways of tenacity and authority. Its advantages are evident. It is much more theoretically sound than the other two, and more in accordance with common sense. Its drawbacks, however, are still more evident. Taste, fashion and different attitudes to life become the foundations of belief, rather than experience and investigation. And that is why, according to Pierce, we need to form yet another way, the way of scientific method, in order to be able to provide solid foundations for our views and theories. The main characteristic of this latter method consists in taking as our point of departure presuppositions which are completely independent of our attitude to them. And Pierce tries to point to examples of such external facts which anyone who thinks critically should be able to ascertain so long as he or she follows certain rules and holds to certain principles.



At this point, however, there arises a difficulty which means that we must part ways with Pierce. The problem is simply this: the way of critical thinking cannot replace the three other ways. Pierce agrees with this: People will always follow the ways of tenacity, authority or prejudice in important matters. And it is exactly this fact which explains how it is possible that someone who has learned to use critical thinking in some areas uses other methods in other fields. The way of scientific method does not release one from the fetters of the other three ways. Pierce, however, says nothing to explain this; he merely points to the way of critical thinking as the only true method for forming a belief. Its advantage, he says, that it alone distinguishes between correct and incorrect methods. “Yes,” Pierce says, “the other methods do have their merits: a clear logical conscience does cost something—just as … all that we cherish, costs us dear.” And he adds that we “need not contemn the others; on the contrary, [we] may honor them deeply, and in doing so [we] only [honor our own method] the more.”

I cannot wholly concur in this attitude, since I wish to go further. The crux of the matter is that we cannot easily choose the way of critical thinking and politely cast the others aside. That would be a dangerous illusion leading to a failure of criticism. Someone who practices critical thinking in his or her own specialty may be entirely dependent upon the other ways in other matters. The illusion consists in thinking that this is not the case and therefore to persist in a fantasy.

Where Pierce goes wrong is when he fails to realize that the other three ways also have their own ways of reaching conclusions and distinguishing between correct and incorrect answers. We may think them completely insufficient or wrong, but our assertion or conviction of this is irrelevant. The truth is that people who use the ways of tenacity, authority and prejudice also continually refer to external facts, in just the same way as we do when we are applying the methods of science and critical thinking. Here we have the crux of the matter. There is no way, is seems, to overcome the other ways. Therefore, it seems natural to choose, as Pierce did, the scientific method and to keep to it from stubbornness alone. However, as I have pointed out, this option is not a practical one; and moreover, it is dangerous in that it causes us to consider ourselves to be independent of the other three ways.

I think that there is only one thing that we can do, or that we ought to do. We should admit that the way of critical thinking is not completely independent with regard to the other three ways, or rather, that it can only be applied in conjunction with them. This applies to science and scholarship as well, for also in these fields the other three ways hold sway. There is one very strong argument for this conclusion. We will never—and let me repeat: never—attain complete certainty about ultimate existence or the conclusive, sufficient grounds in those matters which are the most important to our understanding of reality or our attitude in life. This is a truth about our fundamental assumptions which we come to realize through the application of critical thinking; and it is this truth which constitutes its importance over and above the other three ways; for it is exactly their failure to recognize it that makes them so misleading. The way of tenacity brings one the right views, and so do the ways of authority and prejudice. All of them claim to be giving the “sufficient grounds”, even if they do it in a peculiar manner. That is why it is so dangerous if we employ them by themselves, without being guided by critical thinking.

How should we react to this? What conclusions should we draw with regard to our potential for practicing critical thinking? We only have time for one main point. It is by no means enough to train people in logical reasoning if the aim is to teach them critical thinking. What matters most is that people are taught to discipline their emotions and will in such a way that they never forget to heed the call of critical thinking. Here it is the disciplining of the will which makes all the difference. The human will is infinite, almost divine; but a will which has lost its connection with the emotions and the understanding is a dangerous thing. The emotions then become confused; one may even pretend to emotion which one does not really have. Similarly, one may render judgment on everything between heaven and earth without involving the understanding at all. The human reason is, when all is said and done, nothing but a union of will, understanding and emotion. The exercise of critical thinking has the role of ensuring that this union is a healthy one. And now it is time to embark upon the second stage of this inquiry and to ask: How should we teach critical thinking? As I thank my listeners for their patience, I would like to ask them to contemplate this question.

[1]   Originally a radio lecture, broadcast by Icelandic State Radio (Ríkisútvarpið) on the 13th and 20th of October, 1985; published in Pælingar, Reykjavík: Ergo, 1987, pp. 67–92. [Translated into English by Baldur A. Kristinsson, March 2013.]

[2]   Clifford’s essay first appeared in 1877 in the magazine Contemporary Review. It was reprinted in his Lectures and Essays, London 1879. The Icelandic translation by Þórður Kristinsson is entitled “Rétturinn til sannfæringar” (“The right to have a conviction”); it has not yet been published. [Translator’s note: The translation later appeared in Róbert Haraldsson (ed.): Erindi siðfræðinnar, Rannsóknarstofnun í siðfræði, Reykjavík, 1993, pp. 43–52, as well as in Jacques Maritain et al.: Greinar um heimspeki, translated by Þórður Kristinsson, Háskólaútgáfan, Reykjavík, 1994, pp. 51-59.]

[3]   The Icelandic translation, entitled “Trúarvilji”, is found in the book Máttur manna which was published by Þjóðvinafélagið in 1924 and which also contains two other essays by William James. (The translators of the article were Sig. Kristófer Pétursson and Sigurður Nordal).

[4]   Sigurður Nordal: Líf og dauði, Reykjavík 1940.

[5]   Philosophical Writings of Peirce. Selected and Edited with an Introduction by Justus Buchler, New York 1955, pp. 5-22. (The article originally appeared in 1877.)

[6]   [Translator’s note: Pierce uses the term “the method of the a priori” for what the author here calls “the way of prejudice” (“fordómaleiðin”).]

Back to top