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Critical Thinking

What is Critical Thinking?

What is Critical Thinking?

At the most simple level, critical thinking involves us in making an evaluation or judgment about what we hear or see. For many people, this can just mean making a quick mental decision based on the presenting evidence within a relatively short time frame (or at least within a reasonable period in the busy life that most of us seem to lead today). This approach may work effectively much of the time, especially when the decision has minimal impact on our work or on our life in general. However, the regular use of a “lightly” examined or even an “unexamined” approach may lead to a complacent habit when we hear all arguments that are put to us. And if we are not careful, we may end up with the “unexamined life” that Socrates warned us against over 2500 years ago. In these circumstances, we may easily become hostage to other people’s interpretations of what we should do or how we should live, and we may come to not much like what they have chosen and even feel negatively impacted. For this reason alone, we may want to build our own critical thinking skills to a higher level and develop better and more evolved habits using different and deeper critical thinking approaches, no matter what the argument or the decision that needs to be made.

How has critical thinking evolved?

Before we look at a useful definition that we can work with, let’s consider where the discipline of critical thinking came from historically:

In roughly chronological order, the discipline of Philosophy was probably the first to help define critical thinking as people such as Descartes and the Rational school of philosophy suggested that deep reflection helped mankind to unlock the secrets of its existence.

Mathematics (which was actually a substantial part of Philosophy in the 1600’s) contributed to the development of both algebra and calculus, both of which provide structure to arguments or propositions, which are a significant part of critical thinking theory today.

The field of Music (highly related to mathematics in terms of giving structured or ordered thought and discipline to the production of musical notes) has also made its contribution to critical thinking in suggesting that there are often discoverable “flows” and “patterns” in musical thinking that can be written down and taught.

Education (particularly from the late 19th century and beyond) has increasingly seen deeper reflective and critical thinking to be something that can and should be taught to students in school, usually in a progressive way (with senior school pupils and students at college being the prime targets).

In the early 20th Century Cognitive/Behavioral Psychology also started to look at critical thinking as a discipline and in particular how certain people seemed to naturally have this ability more than  others.

More recently, the discipline of Neuro-science, has contributed to significant advances in better understanding critical thinking in the context of how the brain processes ideas or thought patterns (in both the left and right hemispheres).

Finally, the field of Business has helped to hone critical thinking as a subject area by connecting it specifically to organizationally-focused data-gathering and decision-making processes.

So, what is critical thinking?

In the early 1940’s, Edward Glaser, an expert in the Educational field defined critical thinking as follows:

The ability to think critically involves three things:

  1. an attitude of being disposed to consider in a thoughtful way the problems and subjects that come within the range of one’s experiences,
  2. knowledge of the methods of logical inquiry and reasoning, and
  3. some skill in applying those methods. Critical thinking calls for a persistent effort to examine any belief or supposed form of knowledge in the light of the evidence that supports it and the further conclusions to which it tends.

He went further to say that critical thinking:

“generally requires ability to recognize problems, to find workable means for meeting those problems, to gather and marshal pertinent information, to recognize unstated assumptions and values, to comprehend and use language with accuracy, clarity, and discrimination, to interpret data, to appraise evidence and evaluate arguments, to recognize the existence (or non-existence) of logical relationships between propositions, to draw warranted conclusions and generalizations, to put to test the conclusions and generalizations at which one arrives, to reconstruct one’s patterns of beliefs on the basis of wider experience, and to render accurate judgments about specific things and qualities in everyday life.”

Because Glaser’s definition well stands the test of time, we can conclude then that critical thinking is a form of mental judgment that is specifically purposeful and reflective. As a result, when using critical thinking, an individual makes a decision or solves the problem of judging what to believe or what to do, but does so in a highly reflective or considered way. Critical thinking also gives due consideration to the evidence, the context of judgment, the relevant criteria for making that judgment well, the applicable methods or techniques for forming that judgment, and the applicable theoretical constructs for understanding the nature of the problem and the question or issue at hand.

So, that’s the theory but how do we put this into practice? Well, that’s the subject of a different article on this subject?

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About Dr. Jon Warner

Dr. Jon Warner is a prolific author, management consultant and executive coach with over 25 years experience. He has an MBA and a PhD in Organizational Psychology. Jon can be reached at

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About the Editor and Primary Author

Jon Warner

Jon Warner is an executive coach and management consultant and in the past has been a CEO in three very different companies. Read more

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