by Roy Massie

What should you know to help you navigate through smooth-talkers, deceptive advertising, pushy people in the PTA, cults that knock on your front door and other realities of daily living?  Why can companies sell mil­ lions more cans of sugar water by suggesting that drinking it will make anyone more appealing than they would sell if they did not make that suggestion?    What common fault do lawyers, philosophers, apologists and journalists  often share?  Answer: Informal Fallacies.

The ancient Greeks categorized arguments in various ways (think of an argument like making a rational case for something).  Their categorization included certain patterns of argument that emphasized the form,  or placement of words, within the argument so as to insure that valid con­clusions were drawn from a given set of premises (or rea­sons). Consider this famous argument:


  • All men are mortal.
  • Socrates is a man
  • Therefore, Socrates is a mortal


This argument has a valid form-which  means that it has a structure that guarantees that true premises will lead to a true conclusion.  It would be impossible, that is, for the premises of this argument to be true and its conclusion false.  However, not every argument is valid.  Consider this argument:

  • All men are mortal.
  • All women are mortal.
  • Therefore, all men are women.


Even though the premises of this argument are true, the conclusion is not.  This argument is guilty of a fallacy.  A fallacy is a mistake in reasoning.  The type of fallacy committed by this argument is a formal  fallacy.  This means that there is a flaw in the form or structure of the argument. 1   Guarding against formal fallacies requires that the logic student learn to spot various kinds of flaws in argument structure.

However, not every fallacy is a formal one.  There are also informal  fallacies.  Informal fallacies are not informal in the sense they are “laid back” or “casual.” Rather, they are called informal  because identifying them is impossible by simply inspecting the form of an argument.  To spot an informal fallacy, one must pay careful attention to the content of the argument.  Informal fallacies occur more frequently in everyday life than formal ones.  Therefore, the Christian who wants to avoid errors in reasoning and avoid being deceived by a fallacious argument will spend some time studying informal fallacies.  In this article, we look at several of the most common informal fallacies.



Remember those courtroom dramas where the lawyer insists that the witness simply answer “yes” or “no”?  The witness wants to respond by saying, “I cannot give a yes or no answer; it needs explanation.”  In everyday life, we have to fend for ourselves since there is no attorney to help us present a balanced story.

The danger of being asked a yes or no question, or any question that follows an “either-this-or-that” form, is that it may be a False Dilemma.  The fallacy of False Dilemma occurs when the options have been narrowed down too far.  There are actually more alternatives than you are being told about.  Consider the following:

The edge of the world is either straight or jagged. Either you are for us or you are against us. Nice guys finish last. (either-or implied)

Remedy: The best response to this fallacy is showing a reasonable third alternative that is being overlooked. This deflates the dilemma and opens the door for greater understanding and clarity. Generally, a yes-or-no question can be answered with three possible responses: “Yes,” “No,” and “It depends.”  The “It Depends” response will be followed by some further qualification of the question being asked.

This-or-that type questions are not always bad for clarify­ing a discussion.  Sometimes there really are only two possibilities, but be wary when they are presented to you.



The Bandwagon fallacy replaces evidence and reasoned thinking with a simple appeal to become part of a success­ful or happier group.  It prompts us to rely on a basic emotional need to be accepted, or join the crowd, when a more reasoned and critical response is appropriate. The Bandwagon fallacy is one of the most common in our mass-consumer culture.  Do these sound familiar?

More Americans get their news from XYZ than any other network.

Recent polls indicate that 80% of Americans think God exists.

Over 5 million Bust-A-Waist exercise machines have been sold.

Remedy: Realize that there is a fine line between useful statistics and information intended to sway your opinion. A simple way to test for the Bandwagon fallacy is to ask, “So what does this mean to me?”  What else has been shown to make the suggested course of action relevant to you? If there is only the suggestion you should join the masses, be careful.  Is there a plausible, alternative way to explain the popularity of a given behavior?  Is there a negative aspect not mentioned?   In most cases, knowing what the masses are doing is good information, but rarely is it the most important factor to consider.  If you use pop­ularity statistics in an argument, try to supplement them with other evidence or reasoning that is compelling, irre­spective of popularity.



Of all the fallacies, this one is the most mean-spirited.  In Latin, ad hominem, literally means “against the person,” which is a good description. To commit this fallacy, instead of engaging the substance of the other person’s position, one just criticizes him/her in some personal way (there are several varieties of this fallacy as seen in the following:


One dishonest and unworthy tactic used by several of my detractors is to attribute to me complaints I never made and then to dismiss the “complaints” as “irre­sponsible and evidence of my reckless unfairness.”

– Professional philosopher attacks the character of detractors.

You cannot take him seriously; he is a Bible­ thumper.

– Attacking a stereotype of the position

This sounds like the same nonsense those people at city hall are trying.

-Dismissing a position because of someone else who holds it

What do you expect from someone who eats with tax collectors and sinners?

-Guilt by association

As a rhetorical device, ad hominem attacks may grab the attention of anyone who is listening, but that is about the only nice thing that can be said for them. On their own, they illuminate nothing of relevance within a discussion and can be very harmful.

Remedy: We all know how difficult it can be to stay on course when someone attacks us personally. The coolest heads are able to calmly point out how the ad hominem attack is irrelevant to the subject at hand. If your goal above all else, is to explain your position clearly and calmly, this attitude sometimes helps defuse an ad hominem attack and may gain you a better platform to present your case.



People commit the Straw Man fallacy when they attack an argument different and weaker than the opposition’s actu­al argument (especially avoiding their best argument).

That is, they oversimplify or mischaracterize a position so it is easy to refute.


Christianity is too easy; I just pray a little prayer and then I never have to worry about going to hell.

Liberals just want to raise taxes for bigger government.

Did God really say, “You must not eat from any tree in the garden”? – Serpent, Genesis 3: 1


Remedy:  You will usually know when someone is committing this fallacy against your position.  Just explain how they have oversimplified your view.  With an honest inquirer this might really help.  Moreover, be very careful not to oversimplify subjects you do not understand; this is an unfortunate trait in our nature.  It is common to see straw men made by people who know all about avoiding fallacies. Some people really do hold shallow, immature opinions, but many do not.  Make an effort to understand at least the basics of a subject, and the thinking of some­ one who adheres to it, before posing a challenge.  Asking an informed, carefully directed question is usually more productive than knocking down a straw man that you propped up in the first place.



If you really want to confuse a discussion, perhaps beyond the point of repair, try the fallacy of Equivocation. Equivocation involves the act of using the same word in more than one sense (that is, with multiple meanings) in the same discussion.  Some examples include the follow­ing (the equivocal terms are underlined):


Hot dogs are better than nothing.

Nothing is better than steak.

Therefore, hot dogs are better than steak.


No man will take counsel, but every man will take money: Therefore money is better than counsel. – Jonathan Swift


Do women need to fear man-eating sharks?

Christian: The eyes of God see everything.

Hindu: God is everywhere.

Christian: Yes, He is.

There are many reasons why this fallacy may occur. Sometimes, equivocation is committed by individuals who are not careful.  Worse, some people intentionally seek to be deceitful about what they mean each time they use a certain word.  Other times, each person in a dialog honest­ly thinks he/she knows exactly what the equivocated word means, but his/her conception of it does not match that of the other person.  Both persons are contributing to com­mitting the fallacy since neither has clarified his/her use of the word.

Remedy: Carefully define the key terms of the discussion (especially any technical terms), preferably as soon as they are identified.  Ask the person you are talking to to explain what he means by his terms as well.



This fallacy has a colorful name from a colorful past. When hunters wanted to train their dogs to follow the scent of prey, they would use a dead fish, the Red Herring, whose strong scent would tempt the lesser­ trained dogs to leave the proper target of the hunt.  The Red Herring fallacy is committed when an irrelevant topic or conclusion comes up in an argument, thus diverting attention away from the original subject.


Prosecutor:  Where were you the night of January 17?

Defendant:    I did not enjoy my childhood.


John Doe recently retired from football.  He should be in the Football Hall of Fame because he is kind to small animals and was hall monitor in elementary school.


Christian:  The scientific evidence for the existence of God is very strong.

Atheist:  But, the Bible is full of errors and contra­dictions.


Remedy:  As with most fallacies involving irrelevant infor­mation, the best response is usually pointing out how the information is irrelevant to the discussion at hand. To avoid committing this fallacy, try to insure that your conclusions to arguments, or your responses to questions, are clear enough for someone else to see how they are relevant.



One of the most mind-bending fallacies is Question Begging, also known as begging the question or arguing in a circle.  Question-begging is committed when an argument assumes the truth of its own conclusion in order to establish the conclusion.  Saying the same thing in multi­ple ways does not make a good argument.  These are even hard to describe without talking in a circle, but here are a few examples to ponder:

Mary:     I should go into the tree house first.

Bobby:  Why should you go first?

Mary:   Because I am the leader.

Bobby: Why are you the leader?

Mary:  Because I go in the tree house first.


The Bible is the Word of God.

The Bible says there is a God.

Therefore, God exists.


Many more years of experimentation will likely pass before a laboratory succeeds in actually producing life.  However, the production of life cannot be too difficult, because it happened on Earth apparently as soon as conditions had become suitable for life, around 3.8 billion years ago. –Ernst Mayr, What Evolution Is

The circularity in the first example is pretty clear.  Mary is not supporting the conclusion with anything more than a restatement of the conclusion and an intermediate premise (being the leader), which is also connected to the conclu­sion.  In the second example, you might agree with each premise and the conclusion individually, but still this arrangement  is question-begging.   The conclusion-God exists-is assumed in the premise “The Bible is God’s Word.” A more productive path would be to present a case for God’s existence (or the impossibility of His non-exis­tence) prior to arguing that the Bible is His message to us.

In the third example, a noted biologist argues for the fea­sibility of life arising from non-living matter (without supernatural intervention).  The conclusion, “producing life from non-life is not too difficult,” is assumed in the prem­ise: “it has already happened on Earth without much diffi­culty.”  If we temporarily assume the opposite conclusion (a proper procedure to use): “producing life is incredibly complex, vastly time-consuming, or supernatural,” then the supporting premise is devastated. The scientist may offer other support, but this argument begs the question.

Remedy: Spotting circularities in your own positions and those of others takes practice.   Being aware they exist and trying to avoid them in your own thinking is a good start. Try to organize your thinking so that your conclu­sions are the outcome of premises, which do not depend upon the conclusion. Also note, that all arguments, good or bad, are built upon some assumptions.  It is having the conclusion as one of those assumptions that makes the argument circular.



The fallacies surveyed in this article are only the tip of the iceberg.  There are many more informal fallacies. 2 However, learning these few will go a long way to help­ing the critical reasoner avoid being deceived by faulty reasoning.


Roy Massie is a graduate student in apologetics at Birmingham Theological Seminary.




1  Specifically, this argument commits the formal fallacy known as the “undistributed middle.”  This means that in neither prem­ise is the class referred to in the middle term (“mortal”) referred to in its entirety.  Any valid argument must have a least one premise in which the middle term is distributed.

2 Other informal fallacies are examined in Patrick Hurley, Logic: A Concise Introduction, 91h ed. (Belmont, CA: Wadsw01ih, 2006), 110-183.  See also, Nathaniel and Hans Bluedorn, The Fallacy Detective (Muscatine, IA: Trivium Pursuit, 2002).