Critical thinking practice

I teach in University and run my own research lab. Critical thinking is one of the essential skills I have for my profession. I want students and my lab people to have it through training. Critical thinking is not a knowledge or a unique ability, but a skill developed through training and practice. 

Critical thinking is different from logical thinking. For logical thinking, pre-requisite knowledge is essential to provide an answer. Logical thinking is goal-oriented. Critical thinking is not necessarily aiming for an answer or a goal.  Placing a pause to think about alternative possibilities. 

Logical thinking is equal to judgmental thinking. I mean, a logical person and a judgmental person are not that different. Their difference is the number of judgmental points. The process of logical thinking is represented in flowcharts. A series of yes-or-no. Judgmental thinking has no flow; it's one-shot, yes-or-no. Judgmental thinking can still be logical, but in one shot. Each judgment point of logical thinking is judgmental, yes-or-no, based on knowledge. 

In both cases, when the input is the same, the output is always consistent. Highly reproducible. If knowledge is the same, the output should be the same.

Critical thinking is doubting the reliability of inputs and knowledge. Therefore, the output can be questioned. To communicate these doubts to others after your critical thinking, a logical interpretation of them is required. A new logical structure is necessary for this communication.

I believe that critical thinking is a skill, not an ability. Because it is a skill, everyone can obtain it through training and practice. Critical thinking does not mean doubting everything. Critical thinking does not mean denying everything. Critical thinking does not mean accusing of small details.

The essence of critical thinking is awareness of a gap between senses, cognition and language. As long as we use language, the gap exists. The gap is inevitable, but we pretend it does not exist in language communication in our daily lives. Although we often ignore it, the gap permits alternative possibilities and interpretations. Critical thinking is not about concluding; it is about exploring alternatives. Imagination beyond logic and knowledge is required. For communicating the idea of alternatives to others, a new logical structure is absolutely necessary.

Let’s practice critical thinking with an example. Here is a statement: A guy in a green shirt is playing futsal using a brown soccer ball.

If you are asked whether this statement is correct or not, you have no way to evaluate it. You have to accept it as it is.  To evaluate its correctness, you need to know the original situation that led to this statement. Without the original information, no chance to use the skill of critical thinking.

Here is the original image for this statement. What do you think about my statement?

I do not think I stated anything wrongly. My statement is that a man in a green shirt is playing futsal with a brown soccer ball. 

However, once you see this image with your own eyes, you may have a different opinion about this image. Why does this confusion and discrepancy happen?

We need to realize exactly what we can see. Our visual sense only captures outlines and colours. In this sense, everyone can see green colour, a brown circle and a man-like outline.

Then, I interpret the green colour as a shirt. A brown circle as a brown soccer ball. What you must realize is, when we call a shape or colour in their names, like shirt or ball, they incorporate more than what we can see – their properties and functions. (Properties and functions cannot be seen in a single static image!). A name is often a representation of outline, colours, properties and functions.

Why do I call a brown circle a ball? Because I assumed it, as a brown soccer ball. The word ‘ball’ includes its property that we cannot see but assume as a bit bouncy sphere, not heavy and rigid. ‘Soccer ball’ further includes its use as a ball for playing soccer. Of course, it is impossible to see if the guy is playing anything in a single static image. He might be just standing. Because of the layers of assumptions, I explained as a guy in a green shirt playing futsal with a brown ball. This can be true.  I don’t think anyone can deny this statement from this single image completely.

Many people may assume that this is Jason Tatum in the Celtics playing basketball. But how do they know? This statement also has many assumptions.

After all, this single image alone cannot make any conclusion.

This is the point. The two contradictory statements are both likely (or at least, not entirely rejectable).  Even if people make the same observation, the statements they draw from it can vary and even be contradictory.  If you like classic movies, I recommend watching Akira Kurosawa’s “Rashomon”.  This movie originated from the novel written by Ryunosuke Akutagawa. One murder (supposed to be a murder) and four witnesses. Each has its own story. At the end…. It is not clear if a murder even occurred.

Critical thinking is an awareness of a gap between senses (including observation) and statements (cognition). In communication with language, this gap inevitably occurs. Therefore, not taking the statement fully, but reevaluating raw observation with your own eyes, is important.  This is the realization of others' cognitive processes. You don’t need to agree with them. But you dissect yourself: what exactly you see, what names/words you put on it, and how you interpret it.

What will you do when your statement is different from the original statement?

You have to dig deeper to identify the branching points of diversification. Reevaluate assumptions and interpretations.

Then, you can propose additional information to reconcile/evaluate the discrepancy. Everyone can see a green shirt and a brown circle. But the image looks blurry. You can request better-focused images. To test the possibility of whether he is playing futsal or basketball, you can request different time points on the same view, different view points and wider views to capture the surrounding conditions.

Importantly, a single image cannot allow us to see the properties and functions, but only outlines and colours. Collecting different viewpoints, time points, and scales, and even a continuous movie, would clarify and eliminate alternative possibilities.

Critical thinking is full awareness of the gap between our senses, cognitions and statements.