Some readers may think you have to be smart to think critically. But a corollary is that learning how to think critically makes you smart. The assumption is that one can learn to think critically (that is, be smart). The assumption is correct. Here, I hope to show you how you can become smarter by learning critical thinking skills.
Require Yourself to Think Critically
When you read or listening to others talk, force yourself to become more attentive and engaged with the information. Asking questions assures engagement.
Learn and Look for Common Thinking Errors
Unfortunately, most adults are not taught formal logic, even in college. College logic courses are electives and are made confusing by obtuse premises, propositions, and equations. But common-sense logic can suffice. I have posted a list of common thinking errors elsewhere. Here are some of the more serious thinking errors:
Appeal to authority or consensus: attempting to justify the conclusion by quoting an authority in its support or on the basis of how many people hold the same view.
Argument selectivity: glossing over alternative perspectives (often called “cherry-picking.)” It is not only fair but usually helpful to include opposing positions when making arguments to support a position. Commonly, opposing arguments, even when wrong overall, usually have some grain of truth that needs to be accommodated.
Circular reasoning: reasoning where the premise of an argument or a conclusion is used as support for the argument. Usually, this happens when evidence is missing or glossed over.
Cognitive shortcut bias: doggedly sticking with a favored view or argument for a position, when other more fruitful possibilities exist. Even chess masters, for example, may use an established gambit when a better tactic is available.
Confusing correlation with causation: asserting that when two things happen together, and especially when one occurs just before the other, that one thing causes the other. Without other more direct evidence of causation, this assumption is not justified. Both events could be caused by something else. Example: rain and lightning go together, but neither causes the other.
Exclusivity confusion: failure to recognize elements of compatibility in multiple apparently conflicting ideas or facts. It is important to know whether they are independent, compatible, or mutually exclusive. Example: concepts of evolution and creationism, as they are typically used, are mutually exclusive. However, stated in other ways, they have shared elements of agreement.
False analogy: explaining an idea with an analogy that is not parallel, as in comparing apples and oranges. While analogies and metaphors are powerful rhetorical tools, they are not equivalent to what they reference.
Jumping to conclusions: using only a few facts for a definitive conclusion. The most common situation is failure to consider alternatives. An associated cause is failure to question and test assumptions used to arrive at a conclusion.
Overgeneralization: assuming that what is true for one is true for something else. Example: Some scientists studying free will claim that the decision-making process for making a button press is the same for more complex decisions.
Learn Specific Strategies
Be aware of your thinking. Explain to students the need to think about how they think. This is the art of introspection, focused on being aware of such things as one's own degree of alertness, attentiveness, bias, emotional state, exploration of interpretation options, self-assurance.
Train the ability to focus. In today's multi-tasking world, students commonly lack the ability to concentrate. They are easily distracted. They don't listen well and are not very effective at extracting meaning from what they read.
Use evidence-based reasoning. Don't confuse opinion with fact. When others make a claim, don't accept it without supporting evidence. Even then, look for contrary evidence that is omitted.
Identify what is missing. In conversation or reading, the most important points may be what is not stated. This is especially true when someone is trying to persuade you of their viewpoint.
Ask questions and provide your own answer. I had a professor, C. S. Bachofer at Notre Dame who built a whole course based on this principle. For every reading assignment, he required the students to ask a provocative question about the reading and then write how it might be answered. Fellow students debated each other's questions and answers. Developing this as a thinking habit will ensure you will become a more critical thinker, learn more, and provide some degree of enlightenment to others with whom you interact.
 Klemm, W. R. (2014). Analytical thinking—logic errors 101. http://thankyoubrain.blogspot.com/2014/10/analytical-thinking-logic-err…