Critical Thinking and Logic

Critical thinking is fundamentally a process of questioning information and data. You may question the information you read in a textbook, or you may question what a politician or a professor or a classmate says. You can also question a commonly-held belief or a new idea. With critical thinking, anything and everything is subject to question and examination.

Logic’s Relationship to Critical Thinking

The word logic comes from the Ancient Greek logike, referring to the science or art of reasoning. Using logic, a person evaluates arguments and strives to distinguish between good and bad reasoning, or between truth and falsehood. Using logic, you can evaluate ideas or claims people make, make good decisions, and form sound beliefs about the world.[1]

Questions of Logic in Critical Thinking

Let’s use a simple example of applying logic to a critical-thinking situation. In this hypothetical scenario, a man has a PhD in political science, and he works as a professor at a local college. His wife works at the college, too. They have three young children in the local school system, and their family is well known in the community.

The man is now running for political office. Are his credentials and experience sufficient for entering public office? Will he be effective in the political office? Some voters might believe that his personal life and current job, on the surface, suggest he will do well in the position, and they will vote for him.

In truth, the characteristics described don’t guarantee that the man will do a good job. The information is somewhat irrelevant. What else might you want to know? How about whether the man had already held a political office and done a good job? In this case, we want to ask, How much information is adequate in order to make a decision based on logic instead of assumptions?

The following questions, presented in Figure 1, below, are ones you may apply to formulating a logical, reasoned perspective in the above scenario or any other situation:

  1. What’s happening? Gather the basic information and begin to think of questions.
  2. Why is it important? Ask yourself why it’s significant and whether or not you agree.
  3. What don’t I see? Is there anything important missing?
  4. How do I know? Ask yourself where the information came from and how it was constructed.
  5. Who is saying it? What’s the position of the speaker and what is influencing them?
  6. What else? What if? What other ideas exist and are there other possibilities?
Infographic titled "Questions a Critical Thinker Asks." From the top, text reads: What's Happening? Gather the basic information and begin to think of questions (image of two stick figures talking to each other). Why is it Important? Ask yourself why it's significant and whether or not you agree. (Image of bearded stick figure sitting on a rock.) What Don't I See? Is there anything important missing? (Image of stick figure wearing a blindfold, whistling, walking away from a sign labeled Answers.) How Do I Know? Ask yourself where the information came from and how it was constructed. (Image of stick figure in a lab coat, glasses, holding a beaker.) Who is Saying It? What's the position of the speaker and what is influencing them? (Image of stick figure reading a newspaper.) What Else? What If? What other ideas exist and are there other possibilities? (Stick figure version of Albert Einstein with a thought bubble saying "If only time were relative...".

Figure 1