Student working on mathematical equation.


I will not have my life narrowed down. I will not bow down to somebody else’s whim or to someone else’s ignorance. — bell hooks

If we choose, we can live in a world of comforting illusions. — Noam Chomsky

Critical thinking is arguably more important today than ever before. Many complex and evolving problems await our students – both as professionals and engaged citizens. In today’s world, our students find themselves having to navigate contradictory online sources, competing and increasingly exclusionary political messages, along with an array of forces that pacify rather than encourage meaningful engagement in civic and intellectual life. Critical thinking is an essential skill that our students will need in order to navigate the rough waters ahead.

Learning how to do most things, my dad used to tell me, is a little like learning how to swing a hammer. You have to practice in order to do it well. Having spent this past weekend teaching my own children how to use a hammer, I would have to agree. You can read or listen to someone talk about swinging a hammer, the different minor techniques involved but the only way to really learn how to swing a hammer – is to swing a hammer. The same is true of critical thinking (Brawn, 2004; Tremblay & Downey, 2004). There are important critical thinking principles and techniques to keep in mind (discussed below) but without opportunities to practice, critical thinking will remain an abstract idea.

Principles of critical thinking

What is critical thinking? If you’re drawing a blank, don’t worry – you’re not alone. Turns out that most faculty don’t know what critical thinking is or how to teach it (Paul & Elder, 2013). This gap is understandable considering the abstract nature of critical thinking and lack of unity among scholarly works. Nilson (2014; 2017, pp. 36-37) has identified the common ground among the experts in the field, summarized below.

Critical thinking:

  • Involves an interpretation and judgement about a claim
  • Is difficult, especially when it challenge closely-held beliefs and values
  • May require self-reflection, meta-cognition (thinking about thinking), and self-regulated learning

Critical thinking involves both an interpretation and a judgement about a claim. A claim may be challenged because the evidence is weak or the values underlying the claim are questionable. There may be a conflict of interest – those backing the claim may benefit from its promotion. A claim may also be so firmly integrated into the dominant way of thinking that is almost invisible – a seeming universal truth. This last point highlights the fact that critical thinking is particularly difficult when it challenges closely held beliefs. Our sense of self is based upon our values and beliefs – to question these is to question aspects of who we are. Consequently, many students will be reluctant to deeply engage in critical thought. This is why we must make a strong case for critical thinking – to communicate to our students the consequences of an unquestioning approach to our decisions and stances on issues. Take for example, the issue of climate change. Many people who dispute the well-documented claim that climate change is caused by human activity do not base their argument on evidence, but instead on identity – they do not see themselves as part of a social group or as the kind of person who would believe in an idea like human-caused climate change. This underlines the notion that critical thinking reaches beyond cognitive function – it also involves self-reflection, metacognition (thinking about thinking), and self-regulated learning. Encouraging our students to dig deep and examine why they believe what they believe may help them to put beliefs and ideas to the test – in short, to engage in critically thinking.

Questions and activities to provoke critical thinking

Students may learn the skill of critical thinking through engagement with open-ended questions that involve inquiry, analysis or evaluation. Nilson (2014) has complied the following questions to provoke critical thought:

  • What are your reasons for coming to that interpretation/evaluation?
  • What are the arguments on this issue pro and con?
  • How strong are those arguments? What is the evidence behind them and how solid is it?
  • What are the main assumptions behind this line of reasoning?
  • How can we interpret these data? What conclusions can we draw, if any?
  • What additional information do we need to resolve this issue?
  • What are the trade-offs, implications, and consequences of each solution we’ve discussed?
  • By what standards and priorities will you judge the quality of different solutions?
  • What are the limitations of your chosen solution?
  • How can you defend it against the arguments in favor of other solutions?
  • What are some alternatives that we have not yet explored?

Paul and Elder (2013) have identified eight standards for critical thinking: clarity, accuracy, precision, relevance, depth, breadth, logic, and fairness. Reflecting these standards, they suggest using (or modifying) the following questions:

  • How can you validate the accuracy of this statement/evidence?
  • How is that information relevant here?
  • How well does that conclusion handle the complexities of the problem?
  • What is another interpretation or viewpoint on the issue?
  • How does this conclusion follow from the data or earlier statements?
  • How can both these interpretations be true when they lead to such different conclusions?
  • Do you have a vested interest in one position or another? How honestly and impartially are you representing the other viewpoints?

As with any skill, students require practice and feedback. Here are some examples of critical thinking activities:

Discipline-specific learning outcomes for critical thinking*

Common CT Skills/Outcomes/Assessments in the Basic and Applied Sciences

Which fit your prospective CT course?

  • Interpret quantitative relationships in graphs, tables, charts, etc.
  • Analyze situations/data to identify problems.
  • Identify and summarize the problem/question at issue (and/or the source’s position).
  • Categorize problems to identify the appropriate algorithms.
  • Assess alternative solutions and implement the optimal one(s).
  • Explain how new information can change the definition of a problem or its optimal solution.
  • Evaluate hypotheses for consistency with established facts.
  • Develop and justify one’s own hypotheses, interpretations, or positions.
  • Identify the limitations of one’s own hypotheses, interpretations, or positions.
  • Identify, analyze, and evaluate key assumptions and the influence of context.
  • Evaluate the appropriateness of procedures for investigating a question of causation.
  • Evaluate data for consistency with established facts, hypotheses, or methods.
  • Separate factual information from inferences.
  • Separate relevant from irrelevant information.
  • Identify alternative positions/interpretations of the data or observations.
  • Evaluate competing causal explanations.
  • Explain the limitations of correlational data.
  • Evaluate evidence and identify both reasonable and inappropriate conclusions.
  • Identify and evaluate implications.
  • Identify new information that might support or contradict a hypothesis.

Common CT Skills/Outcomes/Assessments in Technical/Problem Solving Fields (in addition to some of the above)

Which fit your prospective CT course?

  • Separate relevant from irrelevant info.
  • Analyze situations/data to identify problems.
  • Categorize problems to identify the appropriate algorithms.
  • Integrate information/data to solve a problem.
  • Assess alternative solutions and implement the optimal one(s).
  • Explain how new info can change the definition of a problem or its optimal solution.

Common CT Skills/Outcomes/Assessments in Rhetorical Fields (humanities, some areas in social sciences)

Which fit your prospective CT course?

  • Determine the relevance of information for evaluating an argument or conclusion.
  • Separate facts from opinions and inferences.
  • Recognize flaws, inconsistencies, and logical fallacies in an argument.
  • Evaluate competing interpretations, explanations, evidence, and conclusions.
  • Communicate complex ideas effectively.

Common CT Skills/Outcomes/Assessments Distinctive to the Arts

Which fit your prospective CT course?

  • Identify alternative artistic interpretations.
  • Determine how well an artistic interpretation is supported by evidence contained in a work.
  • Recognize the salient features or themes in works of art.
  • Evaluate work of art according to criteria.
  • Compare and contrast different works to provide evidence of change or growth.
  • Infer the historical context (time, place, artist, motivation, etc.) of a work of art from its characteristics, and justify one’s inference.
  • Create a respectable piece of art.

* Source: Nilson, L. (2014). What Activities and Assignments Promote Critical Thinking? Magna Publications, Inc.

Resources and references

Brookfield, S. D. (2012). Teaching for critical thinking: Tools and techniques to help students question their assumptions. San Francisco: Jossey-Bass.

Nilson, L. (2016). Teaching at its best: A research-based resource for college instructors (4th ed.). San Francisco, CA: Jossey-Bass. (Chapter 3)

Nilson, L. (2014). Unlocking the Mystery of Critical Thinking. Faculty Focus.

Paul, R., & Elder, L. (2013). Study of 38 public universities and 28 private universities to determine faculty emphasis on critical thinking in instruction.