Critical Thinking Skills

How are your critical thinking skills? Are you a critical thinker? Or are you a poor thinker, a sloppy thinker, or a rationalizing thinker? Fortunately, poor and sloppy thinking can be corrected more easily than the last. Many very intelligent people seek only to use their thinking to prove what they already believe to be true.

That latter approach is not any part of critical thought. Depending on which psychologist, philosopher, or brain scientist you ask, critical thinking has many definitions, but all of them seem to agree that it includes challenging and analyzing our own motivations, thought processes and conclusions.

What else? Let's start with a basic definition:

"Rational and reflective thinking focused on deciding what to believe and/or how to act."

Rational is not to be confused with logical. Many of the most irrational ideas and actions proceed logically from a chosen set of premises. If you start with certain premises, like a flat Earth, it can be perfectly logical to assume a boat will fall off the edge if it goes too far. Logic simply works from premises to arrive at conclusions systematically, but the premises themselves may be right, wrong, or imperfect.

Rational thought takes into account the possibility that there is not a perfect correspondence between our premises and reality. It starts with observation, evidence gathering, and inductive reasoning. Logic is limited to deductive reasoning, and one bad premise makes all deductions suspect and possibly false. So critical thinking is rational, but challenges that which is simply logical.

Critical thinking is reflective, asking questions like, "Where could I be wrong here? What assumptions am I making and are they justified? What other explanations are there?

For example, suppose on a hot humid day, you think to yourself, "Humidity makes the air feel warmer, and it is normally more humid in Michigan than in Arizona, so if the temperature is the same in both places, it will normally feel warmer in Michigan." The logic is unassailable, but the conclusion is wrong, as I and anyone who has lived in both places in winter can attest to. Humidity actually makes it feel warmer when it is warm and colder when it is cold.

How do you avoid errors like this? You ask if it's true that humidity makes air feel warmer. The experience of a hot day says yes, but because you look for possible errors you note the hidden assumption that "this is always true at any temperature." Because you challenge assumptions, you remember that the hot feeling is in part because your sweat can't evaporate as fast when it is humid, so your body's ability to cool itself is limited. Upon reflection, you realize this wouldn't matter as much when it's cold, because you don't sweat much.

In this case, you might already know enough to see the error and come to a different conclusion. If not, a bit of critical thought would at least point out the need to gather more information and evidence. This example gives you some idea of the mind set of a critical thinker, but what else can you do to develop critical thinking skills? Some suggestions follow.

Cultivating Critical Thinking Skills

Ask For Evidence

Get in the habit of asking for evidence when someone makes a claim. This can be as simple as asking "where did you read that?" or "Was that speculation, or did they test it?" You should also be prepared to provide evidence for your own claims. None of us carries our sources with us, of course, but you should be able to get a sense whether there really is some basis for a claim.

Consider The Source

Since people don't carry evidence around with them, we accept many things said, at least for the sake of argument (otherwise our conversations would be very short, and more like interrogations). But we can consider the sources of the information. Does this person usually remember the facts correctly, and is the source they refer to reliable? Make it a habit to ask yourself these questions.

Consider Motivations

Motivations determine what we believe, what others believe, and what evidence is considered by all of us. Thus, some newspapers and magazines can be entirely slanted in their view, but be motivated to have all of their facts correct. Critical thinking requires that we ask why they have selected these facts to report, and what facts they are leaving out. We should of course ask if there is enough of a motivation for simple dishonesty as well.

Challenge Premises

Habitually reflect on the premises of a claim or argument, whether another's or your own. Actively try to spot weaknesses in them. Remember that one bad premise can taint all that comes from it.

Be Open To Changing Your Mind

Try to always be ready and willing to change your mind based on new evidence. In the sciences, critical thinking is crucial, and a good scientist is ready and willing to drop the beliefs of a lifetime if better ones present themselves. Make it a point to ask yourself what evidence would change your mind. This prepares you for the possibility.

Consider Your Own Experience

I heard someone make a claim that is "politically correct" the other day. As is common with such claims, it is assumed that everyone agrees. But just a moments reflection made me realize that my own experience refuted the claim. Compare what is said to your own knowledge and experience.

Look For Common Logical Fallacies

Try to habitually identify common logical fallacies and errors. For example, if you ever hear an argument based on what some "expert" or "authority" said, immediately dismiss it. The claim may be true, but look for other ways to verify it. An "appeal to authority" is a logical fallacy based on the hidden assumption that "If he said it, it must be true." Respect for an authority may suggest a closer look at the evidence, but should not be considered strong evidence by itself. Watch for this and other logical errors.

Admit Ignorance

Critical thinking requires us to confess our ignorance, at least to ourselves. A common response to not understanding something is to invent an explanation (this is the whole basis for most claims of "psychic powers"). A better way is to habitually say, "Hmm... I don't know. I'm not sure. I'll wait for more information or evidence." Speculation has its place, but when speculation becomes explanation, it stops the search for truth and prevents the truth from even being seen when it becomes evident.

Look For Alternative Explanations

You mind should be thinking like this: "Hmm... I can see that this explanation makes sense, but what other explanations are possible?" Of course, when other possibilities do present themselves, you should then be willing to look at the evidence for these. This is how you develop critical thinking skills.