What Are the Differences Between Bias & Fallacy?

by Ginger Voight Google

To sharpen your critical thinking skills, you must understand how you communicate your ideas to others, as well as how you process information being communicated to you. Two common reasoning problems include fallacies and biases. Since both practices are commonly used in debates and the exchange of ideas, it is important to recognize how these logic flaws are used to manipulate the message and undercut a debate.


Biases affect how you interpret and collect information and can lead to flawed reasoning. Yet it is a typical part of human psychology as people tend to process information through the filter of their own perception. Biases result from personal experience and ideology, such as political or religious influence, and these biases lead people to believe information that supports what they already perceive to be true, rather than test their own point of view against contradicting evidence.


Whereas biases affect how you take in information, fallacies affect how you communicate your thoughts and ideas to others. A fallacy indicates a reasoning mistake and flawed logic used to support a particular point of view. In these arguments, you may make conclusions based on information that has nothing to do with the original topic, or defend your position by attacking your opponent rather than presenting facts that support your own position.

Fallacy Examples

There are several types of fallacy arguments. An "ad hominem" fallacy attacks the messenger, rather than a message itself. This assumes that the characteristics of the opponent nullify the argument, whether or not they pertain to the argument at all. The "straw man" fallacy raises the comparison with implausible hyperbole that, when refuted, supposedly refutes the original point. A "slippery slope" fallacy suggests that if one claim is true, then all subsequent claims, no matter how outlandish, must be true as well.

Detecting Bias

Because bias is so prevalent, the challenge is deciphering what biases may be at play behind the information being presented. Ask yourself what the speaker/writer has to gain from presenting the information in the way she is presenting it. Ask yourself whether or not the speaker/writer is invested in presenting a point of view a certain way, such as being involved in a group that would benefit from a biased presentation. Research the facts being presented to see if the argument is an aforementioned fallacy and if the statistics are from equally biased sources.

Photo Credits

  • Goodshoot/Goodshoot/Getty Images