Everyone thinks, but not everyone is a critical thinker. For, at its most basic level, thinking is simply the firing of synapses in the brain, and these electrical impulses control a body’s most basic functions, from letting it know when it’s hungry to controlling its every movement.
At its more advanced level, however, thinking is a purposeful, organized cognitive process that is used to make sense of one’s environment. It is also an active cognitive process that involves reasoning and judgment and through which people evaluate their ideas, habits, and belief systems through the application of logic. Moreover, the ability to think critically allows people to make intelligent decisions, solve problems, and achieve goals.
The two methods of reasoning that people use when forming conclusions are inductive and deductive.
What is Inductive Reasoning?
An argument using inductive reasoning is one wherein people reason from premises that are known or assumed to be true to form a conclusion that is supported by the premises but does not necessarily follow from those premises (Chaffee, 2000).
In other words, when people reason inductively, their premises provide evidence that makes it more or less probable (but not certain) that the conclusion they reach is true. For example:
- Tom’s three cousins had upset stomachs after the family reunion, which were probably caused by Aunt Grace’s tuna fish salad.
- On the average, people with college degrees will earn a million dollars more in their lifetimes than people possessing only high school diplomas.
The first statement is an example of casual reasoning, a form of inductive reasoning where someone claims that an event is the result of another event (Chaffee, 2000). However, although the cousins’ upset stomachs could have been triggered by Aunt Grace’s tuna fish salad, since there is no proof to substantiate this claim, Uncle Frank’s barbecued chicken could have been the culprit, or it could have been something the cousins ate before or after the reunion.
The second statement, on the other hand, is an example of an empirical generalization, a general statement someone makes about an entire group on the basis of observing only some members of the group (Chaffee, 2000).
In reality, though, even if some people with college degrees will earn a million dollars more in their lifetimes than some people possessing only high school diplomas, some will earn far less and some will earn far more. Plus, some people with only high school diplomas could possibly earn far more than some people with college degrees.
What is Deductive Reasoning?
An argument using deductive reasoning is one wherein people reason from premises that are known or assumed to be true to form a conclusion that necessarily follows from those premises.
In deductive reasoning, the truth of the premises guarantees the truth of the conclusion (Chaffee, 2000). Moreover, since one accepts the premises of the argument as true, this means the conclusion cannot be false.
Many deductive arguments are structured as syllogisms, an argument form that consists of two supporting premises and a conclusion, for example:
- Premise: All men are mortal
- Premise: Socrates is a man
- Conclusion: Therefore, Socrates is mortal
What one must bear in mind, however, is that there are invalid deductive forms of reasoning, for example:
- Premise: All politicians are corrupt
- Premise: John Smith is a politician
- Conclusion: Therefore, John Smith is corrupt
The problem with this argument is that while some politicians may be corrupt, not all politicians are corrupt; moreover, unless one personally knows John Smith, how can one judge Smith’s ethics or lack thereof?
This form of pseudo-reasoning (false reasoning) is called a fallacy, which is an argument that is unsound because it is based upon illogical, often biased, premises that do not support the conclusion. This type of reasoning, though, is often used to influence people by appealing to them on the basis of emotional factors, such as prejudice, dislike, or envy, etc. Moreover, fallacious reasoning supports conclusions someone, for various reasons, wants to believe are true.
Becoming a Critical Thinker
In order to become critical thinkers people need to ask if the arguments with which they are being presented, as well as those they themselves are presenting, actually make sense. Moreover, they need to ask under what conditions might those arguments be true but under what conditions might they instead be false.
Additionally, people should identify any assumptions (preconceived beliefs underlying their points of view) that might influence their conclusions and, finally, assess the accuracy and the validity of the evidence that is being presented in support of an argument.
By failing to think critically, people accept as true their own biases and illogically formed conclusions as well as whatever they are told by other people, for example, politicians, televisions commercials, religious leaders, and news organizations. In other words, people who not think critically accept as true what may very well instead be a half-truth or even an out-and-out lie.
Sources:
- Chaffee, J. (2000) Thinking Critically: Sixth Edition. Houghton Mifflin: New York.
Carol Rzadkiewicz - Carol Rzadkiewicz has taught college English for over 14 years and is the author of three published novels and numerous short stories.
