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Justifiable Need Definition For Critical Thinking


To be skilled in critical thinking is to be able to take one’s thinking apart systematically, to analyze each part, assess it for quality and then improve it. The first step in this process is understanding the parts of thinking, or elements of reasoning.

These elements are: purpose, question, information, inference, assumption, point of view, concepts, and implications. They are present in the mind whenever we reason. To take command of our thinking, we need to formulate both our purpose and the question at issue clearly. We need to use information in our thinking that is both relevant to the question we are dealing with, and accurate. We need to make logical inferences based on sound assumptions. We need to understand our own point of view and fully consider other relevant viewpoints. We need to use concepts justifiably and follow out the implications of decisions we are considering. (For an elaboration of the Elements of Reasoning, see a Miniature Guide to the Foundations of Analytic Thinking.)

In this article we focus on two of the elements of reasoning: inferences and assumptions. Learning to distinguish inferences from assumptions is an important intellectual skill. Many confuse the two elements. Let us begin with a review of the basic meanings:

  1. Inference: An inference is a step of the mind, an intellectual act by which one concludes that something is true in light of something else’s being true, or seeming to be true. If you come at me with a knife in your hand, I probably would infer that you mean to do me harm. Inferences can be accurate or inaccurate, logical or illogical, justified or unjustified.

  2. Assumption: An assumption is something we take for granted or presuppose. Usually it is something we previously learned and do not question. It is part of our system of beliefs. We assume our beliefs to be true and use them to interpret the world about us. If we believe that it is dangerous to walk late at night in big cities and we are staying in Chicago, we will infer that it is dangerous to go for a walk late at night. We take for granted our belief that it is dangerous to walk late at night in big cities. If our belief is a sound one, our assumption is sound. If our belief is not sound, our assumption is not sound. Beliefs, and hence assumptions, can be unjustified or justified, depending upon whether we do or do not have good reasons for them. Consider this example: “I heard a scratch at the door. I got up to let the cat in.” My inference was based on the assumption (my prior belief) that only the cat makes that noise, and that he makes it only when he wants to be let in.

We humans naturally and regularly use our beliefs as assumptions and make inferences based on those assumptions. We must do so to make sense of where we are, what we are about, and what is happening. Assumptions and inferences permeate our lives precisely because we cannot act without them. We make judgments, form interpretations, and come to conclusions based on the beliefs we have formed.

If you put humans in any situation, they start to give it some meaning or other. People automatically make inferences to gain a basis for understanding and action. So quickly and automatically do we make inferences that we do not, without training, notice them as inferences. We see dark clouds and infer rain. We hear the door slam and infer that someone has arrived. We see a frowning face and infer that the person is upset. If our friend is late, we infer that she is being inconsiderate. We meet a tall guy and infer that he is good at basketball, an Asian and infer that she will be good at math. We read a book, and interpret what the various sentences and paragraphs — indeed what the whole book — is saying. We listen to what people say and make a series of inferences as to what they mean.

As we write, we make inferences as to what readers will make of what we are writing. We make inferences as to the clarity of what we are saying, what requires further explanation, what has to be exemplified or illustrated, and what does not. Many of our inferences are justified and reasonable, but some are not.

As always, an important part of critical thinking is the art of bringing what is subconscious in our thought to the level of conscious realization. This includes the recognition that our experiences are shaped by the inferences we make during those experiences. It enables us to separate our experiences into two categories: the raw data of our experience in contrast with our interpretations of those data, or the inferences we are making about them. Eventually we need to realize that the inferences we make are heavily influenced by our point of view and the assumptions we have made about people and situations. This puts us in the position of being able to broaden the scope of our outlook, to see situations from more than one point of view, and hence to become more open-minded.

Often different people make different inferences because they bring to situations different viewpoints. They see the data differently. To put it another way, they make different assumptions about what they see. For example, if two people see a man lying in a gutter, one might infer, “There’s a drunken bum.” The other might infer, “There’s a man in need of help.” These inferences are based on different assumptions about the conditions under which people end up in gutters. Moreover, these assumptions are connected to each person’s viewpoint about people. The first person assumes, “Only drunks are to be found in gutters.” The second person assumes, “People lying in the gutter are in need of help.”

The first person may have developed the point of view that people are fundamentally responsible for what happens to them and ought to be able to care for themselves. The second may have developed the point of view that the problems people have are often caused by forces and events beyond their control. The reasoning of these two people, in terms of their inferences and assumptions, could be characterized in the following way:

Person One

Person Two

Situation: A man is lying in the gutter.

Situation: A man is lying in the gutter.

Inference: That man’s a bum. Inference: That man is in need of help.

Assumption: Only bums lie in gutters.

Assumption: Anyone lying in the gutter is in need of help.


Critical thinkers notice the inferences they are making, the assumptions upon which they are basing those inferences, and the point of view about the world they are developing. To develop these skills, students need practice in noticing their inferences and then figuring the assumptions that lead to them.

As students become aware of the inferences they make and the assumptions that underlie those inferences, they begin to gain command over their thinking. Because all human thinking is inferential in nature, command of thinking depends on command of the inferences embedded in it and thus of the assumptions that underlie it. Consider the way in which we plan and think our way through everyday events. We think of ourselves as preparing for breakfast, eating our breakfast, getting ready for class, arriving on time, leading class discussions, grading student papers, making plans for lunch, paying bills, engaging in an intellectual discussion, and so on. We can do none of these things without interpreting our actions, giving them meanings, making inferences about what is happening.

This is to say that we must choose among a variety of possible meanings. For example, am I “relaxing” or “wasting time?” Am I being “determined” or “stubborn?” Am I “joining” a conversation or “butting in?” Is someone “laughing with me” or “laughing at me?” Am I “helping a friend” or “being taken advantage of?” Every time we interpret our actions, every time we give them a meaning, we are making one or more inferences on the basis of one or more assumptions.

As humans, we continually make assumptions about ourselves, our jobs, our mates, our students, our children, the world in general. We take some things for granted simply because we can’t question everything. Sometimes we take the wrong things for granted. For example, I run off to the store (assuming that I have enough money with me) and arrive to find that I have left my money at home. I assume that I have enough gas in the car only to find that I have run out of gas. I assume that an item marked down in price is a good buy only to find that it was marked up before it was marked down. I assume that it will not, or that it will, rain. I assume that my car will start when I turn the key and press the gas pedal. I assume that I mean well in my dealings with others.

Humans make hundreds of assumptions without knowing it---without thinking about it. Many assumptions are sound and justifiable. Many, however, are not. The question then becomes: “How can students begin to recognize the inferences they are making, the assumptions on which they are basing those inferences, and the point of view, the perspective on the world that they are forming?”

There are many ways to foster student awareness of inferences and assumptions. For one thing, all disciplined subject-matter thinking requires that students learn to make accurate assumptions about the content they are studying and become practiced in making justifiable inferences within that content. As examples: In doing math, students make mathematical inferences based on their mathematical assumptions. In doing science, they make scientific inferences based on their scientific assumptions. In constructing historical accounts, they make historical inferences based on their historical assumptions. In each case, the assumptions students make depend on their understanding of fundamental concepts and principles.

As a matter of daily practice, then, we can help students begin to notice the inferences they are making within the content we teach. We can help them identify inferences made by authors of a textbook, or of an article we give them. Once they have identified these inferences, we can ask them to figure out the assumptions that led to those inferences. When we give them routine practice in identifying inferences and assumptions, they begin to see that inferences will be illogical when the assumptions that lead to them are not justifiable. They begin to see that whenever they make an inference, there are other (perhaps more logical) inferences they could have made. They begin to see high quality inferences as coming from good reasoning.

We can also help students think about the inferences they make in daily situations, and the assumptions that lead to those inferences. As they become skilled in identifying their inferences and assumptions, they are in a better position to question the extent to which any of their assumptions is justified. They can begin to ask questions, for example, like: Am I justified in assuming that everyone eats lunch at 12:00 noon? Am I justified in assuming that it usually rains when there are black clouds in the sky? Am I justified in assuming that bumps on the head are only caused by blows?

The point is that we all make many assumptions as we go about our daily life and we ought to be able to recognize and question them. As students develop these critical intuitions, they increasingly notice their inferences and those of others. They increasingly notice what they and others are taking for granted. They increasingly notice how their point of view shapes their experiences.

 

This article was adapted from the book, Critical Thinking: Tools for Taking Charge of Your Learning and Your Life, by Richard Paul and Linda Elder.

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Why Critical Thinking?

The Problem

Everyone thinks. It is our nature to do so. But much of our thinking, left to itself, is biased, distorted, partial, uninformed, or downright prejudiced. Yet, the quality of our life and that of what we produce, make, or build depends precisely on the quality of our thought. Shoddy thinking is costly, both in money and in quality of life. Excellence in thought, however, must be systematically cultivated.


A Definition

Critical thinking is that mode of thinking — about any subject, content, or problem — in which the thinker improves the quality of his or her thinking by skillfully analyzing, assessing, and reconstructing it. Critical thinking is self-directed, self-disciplined, self-monitored, and self-corrective thinking. It presupposes assent to rigorous standards of excellence and mindful command of their use. It entails effective communication and problem-solving abilities, as well as a commitment to overcome our native egocentrism and sociocentrism.

To Analyze Thinking

Identify its purpose, and question at issue, as well as its information, inferences(s), assumptions, implications, main concept(s), and point of view.

To Assess Thinking

Check it for clarity, accuracy, precision, relevance, depth, breadth, significance, logic, and fairness.

The Result

A well-cultivated critical thinker:

  • Raises vital questions and problems, formulating them clearly and precisely
  • Gathers and assesses relevant information, using abstract ideas to interpret it effectively
  • Comes to well-reasoned conclusions and solutions, testing them against relevant criteria and standards
  • Thinks openmindedly within alternative systems of thought, recognizing and assessing, as needs be, their assumptions, implications, and practical consequences
  • Communicates effectively with others in figuring out solutions to complex problems


The Etymology & Dictionary Definition of "Critical Thinking"

The concept of critical thinking we adhere to reflects a concept embedded not only in a core body of research over the last 30 to 50 years but also derived from roots in ancient Greek. The word ’’critical’’ derives etymologically from two Greek roots: "kriticos" (meaning discerning judgment) and "kriterion" (meaning standards). Etymologically, then, the word implies the development of "discerning judgment based on standards."

In Webster’s New World Dictionary, the relevant entry reads "characterized by careful analysis and judgment" and is followed by the gloss, "critical — in its strictest sense — implies an attempt at objective judgment so as to determine both merits and faults." Applied to thinking, then, we might provisionally define critical thinking as thinking that explicitly aims at well-founded judgment and hence utilizes appropriate evaluative standards in the attempt to determine the true worth, merit, or value of something.

The tradition of research into critical thinking reflects the common perception that human thinking left to itself often gravitates toward prejudice, over-generalization, common fallacies, self-deception, rigidity, and narrowness.

The critical thinking tradition seeks ways of understanding the mind and then training the intellect so that such "errors", "blunders", and "distortions" of thought are minimized. It assumes that the capacity of humans for good reasoning can be nurtured and developed by an educational process aimed directly at that end.

The history of critical thinking documents the development of this insight in a variety of subject matter domains and in a variety of social situations. Each major dimension of critical thinking has been carved out in intellectual debate and dispute through 2400 years of intellectual history.

That history allows us to distinguish two contradictory intellectual tendencies: a tendency on the part of the large majority to uncritically accept whatever was presently believed as more or less eternal truth and a conflicting tendency on the part of a small minority — those who thought critically — to systematically question what was commonly accepted and seek, as a result, to establish sounder, more reflective criteria and standards for judging what it does and does not make sense to accept as true.

Our basic concept of critical thinking is, at root, simple. We could define it as the art of taking charge of your own mind. Its value is also at root simple: if we can take charge of our own minds, we can take charge of our lives; we can improve them, bringing them under our self command and direction. Of course, this requires that we learn self-discipline and the art of self-examination. This involves becoming interested in how our minds work, how we can monitor, fine tune, and modify their operations for the better. It involves getting into the habit of reflectively examining our impulsive and accustomed ways of thinking and acting in every dimension of our lives.

All that we do, we do on the basis of some motivations or reasons. But we rarely examine our motivations to see if they make sense. We rarely scrutinize our reasons critically to see if they are rationally justified. As consumers we sometimes buy things impulsively and uncritically, without stopping to determine whether we really need what we are inclined to buy or whether we can afford it or whether it’s good for our health or whether the price is competitive. As parents we often respond to our children impulsively and uncritically, without stopping to determine whether our actions are consistent with how we want to act as parents or whether we are contributing to their self esteem or whether we are discouraging them from thinking or from taking responsibility for their own behavior.

As citizens, too often we vote impulsively and uncritically, without taking the time to familiarize ourselves with the relevant issues and positions, without thinking about the long-run implications of what is being proposed, without paying attention to how politicians manipulate us by flattery or vague and empty promises. As friends, too often we become the victims of our own infantile needs, "getting involved" with people who bring out the worst in us or who stimulate us to act in ways that we have been trying to change. As husbands or wives, too often we think only of our own desires and points of view, uncritically ignoring the needs and perspectives of our mates, assuming that what we want and what we think is clearly justified and true, and that when they disagree with us they are being unreasonable and unfair.

As patients, too often we allow ourselves to become passive and uncritical in our health care, not establishing good habits of eating and exercise, not questioning what our doctor says, not designing or following good plans for our own wellness. As teachers, too often we allow ourselves to uncritically teach as we have been taught, giving assignments that students can mindlessly do, inadvertently discouraging their initiative and independence, missing opportunities to cultivate their self-discipline and thoughtfulness.

It is quite possible and, unfortunately, quite "natural" to live an unexamined life; to live in a more or less automated, uncritical way. It is possible to live, in other words, without really taking charge of the persons we are becoming; without developing or acting upon the skills and insights we are capable of. However, if we allow ourselves to become unreflective persons — or rather, to the extent that we do — we are likely to do injury to ourselves and others, and to miss many opportunities to make our own lives, and the lives of others, fuller, happier, and more productive.

On this view, as you can see, critical thinking is an eminently practical goal and value. It is focused on an ancient Greek ideal of "living an examined life". It is based on the skills, the insights, and the values essential to that end. It is a way of going about living and learning that empowers us and our students in quite practical ways. When taken seriously, it can transform every dimension of school life: how we formulate and promulgate rules; how we relate to our students; how we encourage them to relate to each other; how we cultivate their reading, writing, speaking, and listening; what we model for them in and outside the classroom, and how we do each of these things.

Of course, we are likely to make critical thinking a basic value in school only insofar as we make it a basic value in our own lives. Therefore, to become adept at teaching so as to foster critical thinking, we must become committed to thinking critically and reflectively about our own lives and the lives of those around us. We must become active, daily, practitioners of critical thought. We must regularly model for our students what it is to reflectively examine, critically assess, and effectively improve the way we live.

Critical thinking is that mode of thinking — about any subject, content, or problem — in which the thinker improves the quality of his or her thinking by skillfully analyzing, assessing, and reconstructing it. Critical thinking is self-directed, self-disciplined, self-monitored, and self-corrective thinking. It presupposes assent to rigorous standards of excellence and mindful command of their use. It entails effective communication and problem-solving abilities, as well as a commitment to overcome our native egocentrism and sociocentrism.

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