Recognizing Fallacies/Fallacies of Presumption

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Fallacies of Presumption[edit]

Fallacies of presumption are arguments that depend on some assumption that is typically unstated and unsupported. Identifying the implicit assumption often exposes the fallacy.

Complex Question[edit]

A complex question, or plurium interrogationum (Latin, “of many questions”) is a question that has a presupposition—an implicit assumption assumed to be true—that is complex because it contains several subparts. A question is complex when it is asked in such a way as to presuppose the truth of some conclusion buried in the question.[1] A complex question is a loaded question if affirming the implicit assumption is detrimental to the person answering the question.

This fallacy has the form of a question with a false, disputed, or circular (begging the question) presumption.[2]

This fallacy is often illustrated by the question “Have you stopped beating your wife?” The question presupposes that you have beaten your wife prior to its asking, as well as presupposing that you have a wife. If you have no wife, or have never beaten your wife, then the question is loaded.

Since this example is a yes/no question, there are only the following two direct answers:

  • "Yes, I have stopped beating my wife", which entails "I was beating my wife."
  • "No, I haven't stopped beating my wife", which entails "I am still beating my wife."

Thus, either direct answer entails that you have beaten your wife, which is, therefore, a presupposition of the question. So, a loaded question is one which you cannot answer directly without implying a falsehood or a statement that you deny. For this reason, the proper response to such a question is not to answer it directly, but to either refuse to answer or to identify the fallacy and reject the question.[3]

Some systems of parliamentary debate provide for “dividing the question”, that is, splitting a complex question up into two or more simple questions. Such a move can be used to split the example as follows:

  1. "Have you ever beaten your wife?"
  2. "If so, are you still doing so?"

In this way, 1 can be answered directly by "no", and then the conditional question 2 does not arise.[4]

A complex question is only a fallacy if it presumes a disputed assumption. Hence we can distinguish between:

  • legitimately complex questions (not a fallacy): A question that assumes something that the hearer would readily agree to. For example, "Who is the monarch of the United Kingdom?" assumes that there is a place called the United Kingdom and that it has a monarch, both true.
  • illegitimately complex question: On the other hand, "Who is the King of France?" would commit the complex question fallacy because while it assumes there is a place called France (true), it also assumes France currently has a king (false). But since answering this question does not seem to incriminate or otherwise embarrass the speaker, it is complex but not really a loaded question.

Complex questions are often used to trap opponents during a public forum, debate, or interview. Here are some prominent examples.

Madeleine Albright regrets failing to recognize a complex question posed by Lesley Stahl.

Madeleine Albright (U.S. Ambassador to the U.N.) fell into a trap of answering a loaded question (and later regretted not challenging it instead) on 60 Minutes on 12 May 1996. Lesley Stahl asked, regarding the effects of UN sanctions against Iraq, "We have heard that a half million children have died. I mean, that is more children than died in Hiroshima. And, you know, is the price worth it?" Madeleine Albright: "I think that is a very hard choice, but the price, we think, the price is worth it."[5] She later wrote of this response:

I must have been crazy; I should have answered the question by reframing it and pointing out the inherent flaws in the premise behind it.... As soon as I had spoken, I wished for the power to freeze time and take back those words. My reply had been a terrible mistake, hasty, clumsy, and wrong.... I had fallen into a trap and said something that I simply did not mean. That is no one's fault but my own.[6]

In another example, the New Zealand corporal punishment referendum, 2009 asked: "Should a smack as part of good parental correction be a criminal offence in New Zealand?" Murray Edridge, of Barnardos New Zealand, criticized the question as "loaded and ambiguous" and claimed "the question presupposes that smacking is a part of good parental correction"[7]

False Dilemma[edit]

The fallacy of false dilemma is a form of the complex question fallacy.

A false dilemma is a type of informal fallacy that involves a situation in which only limited alternatives are considered, when in fact there is at least one additional option. Other names for this fallacy include: false dichotomy, false binary, black-and-white thinking, bifurcation, denying a conjunct, the either-or fallacy, fallacy of exhaustive hypotheses, the fallacy of false choice, or the fallacy of the false alternative.

The fallacy takes on the following form:[8]

Either claim X is true or claim Y is true (when X and Y could both be false).
Claim Y is false.
Therefore claim X is true.

This is the fallacy of thinking that things are either black or white, good or bad, all or nothing.[9] This fallacy can lead to rigid and harmful rules based on primal thinking when it is efficient to compress complex information into simplistic categories for rapid decision making during times of stress, conflict, or threat. Polarized thinking can also lead to unhelpful forms of perfectionism. The reality often lies in the sizeable middle ground between these extreme poles. Recognize and reject the false dichotomy. The words “either / or” are a reliable signal alerting us to a false dichotomy. Find other alternatives that provide a constructive solution. Dialogue is a powerful tool for moving beyond a false dichotomy. A clever Zen master teaches his students to reject a false dichotomy and go beyond polarized thinking with the following challenge. He places a cup of tea before the student, then says “If you drink that cup of tea, I will beat you with a stick, and if you don't drink that cup of tea I will beat you with a stick.” The student has to reject the false dichotomy, recognize options other than the two presented, and create other alternatives, such as offering the tea to the instructor, or asking his advice, to avoid punishment.

Some phenomena are intrinsically dual

Some phenomena are intrinsically dual. Consider the image on the right, known as the Rubin vase / profile illusion. Do you see a vase or two human profiles looking at each other eye to eye? An optical illusion—demonstrating a surprising feature or limitation of our visual perception system—causes us to see either the vase or the faces at any one time. This is determined by perceiving either the black as the foreground and the white as the background, or vice versa, at any instance. This perception easily flips as our attention shifts and we see the other image. We cannot see both at once and we can voluntarily see either one at a given time. What we see is an image that can be perceived as either at any particular instance. Arguing for vase vs. face misses the point; the image is intrinsically both. Focusing on the false dichotomy of face or vase distracts us from understanding the intrinsic duality of face and vase. Quantum physics elegantly describes how light is both wave and particle. Asking if Barack Obama is black or white, if you are liberal or conservative, republican or democrat, with us or against us, scientific or religious, can obscure a grander unity.

Everyday language includes many subtle false dichotomies. Asking “do the ends justify the means” focuses on a false choice between these ends and those means. It dismisses the important possibilities of achieving important goals by other, less destructive means. Asking “whose fault is this” encourages us to choose a single person to blame. Justifying actions by saying “I had no choice” falsely dismisses the many alternatives that were not imagined and not chosen. Asking if a particular behavior results from “nature or nurture” distracts us from recognizing that most behavior results from a combination of both. Concluding “you get what you pay for” dismisses the possibility of market inefficiencies or breakthroughs in product design, manufacturing techniques, or discovering new value and new types of value in unusual places.

False dichotomies are harmful because they distract us from the many alternatives that could provide creative solutions or help us constructively resolve conflict. Consider the distinction between the false dichotomy of “black or white” and the accurate dichotomy of “black or non-black”. Non-black includes a vast range of colors spanning shades of gray, the colors of the rainbow, and the infinite shades of colors in between. Yet all of these rich and varied possibilities are dismissed when we accept the false dichotomy of “black or white”. The red rose, green grass, blue sky, and golden sunshine all disappear when we focus narrowly on “black or white” rather than “black or non-black”.

Non-black includes a vast range of colors spanning shades of gray, the colors of the rainbow, and the infinite shades of colors in between

False dichotomies confuse complements with opposites. The complement of black is non-black, which includes a wide range of colors. The opposite of black is anti-black, which is the single color we call white.

Using the phrase “I think of this somewhat differently . . .” can create a useful transition when you are confronted with a false dilemma or a question based on false assumptions. It creates space for introducing an alternative viewpoint and moving the conversation in a more constructive direction.

False Cause[edit]

It may be helpful to begin this section by viewing this Khan Academy video on the Post Hoc Ergo Proper Hoc fallacy.

It is a fallacy to conclude that one event is a cause of another without providing relevant evidence of the causal link. Causality is difficult to determine, and is a central topic in inductive logic and in scientific methods. False cause fallacies occur in several forms and are classified according to the association the alleged cause has to its alleged effect.

Post hoc ergo propter hoc (Latin: "after this, therefore because of this") is a logical fallacy that states "Since event Y followed event X, event Y must have been caused by event X." It is often shortened to simply post hoc fallacy. The fallacy lies in coming to a conclusion based solely on the order of events, rather than taking into account other factors that might rule out the connection.

The form of the post hoc fallacy can be expressed as follows:

A occurred, then B occurred.
Therefore, A caused B.

When B is undesirable, this pattern is often extended to the reverse: Avoiding A will prevent B.

Concluding that a rainstorm was caused by a rain dance is an example of this fallacy. This fallacy sneaks in when ‘the sun rose after the rooster crows’ becomes ‘the sun rose because the rooster crows’. In fact, causality is a complex topic and is difficult to prove. John Stewart Mills proposed his “canons of induction” also known as “Mills Methods” as a test for establishing that “A” causes “B”. This is an important basis for scientific methods. Be careful to use the word “because” only to describe a cause and effect relationship that you know exists.

This fallacy sustains many superstitions and other forms of pseudoscience. It is also used to support or oppose various policy decisions. For example after a tax increase many changes will occur in the local, regional, national, and global economies in the short term and in the long term. Proponents of the tax increase can point to favorable outcomes and claim credit for those positive effects. Opponents can point to unfavorable outcomes and cast blame for those negative effects. It is unlikely that causality has been demonstrated in either case.

In a May 30, 2012, conference call with reporters, Reince Priebus said that because of voter fraud, Republican candidates “need to do a point or two better” to win statewide elections in Wisconsin.[10] This is a fallacy because: 1) There is no evidence of voter fraud, and 2) There is no evidence of any connection between alleged voter fraud and election outcomes.

Cum Hoc, Ergo Propter Hoc (Latin for “with this, therefore because of this”) is a logical fallacy that states "Since event Y is coincident with event X, event Y must have been caused by event X." The fallacy lies in coming to a conclusion based solely on the proximity of events, rather than taking into account other factors that might rule out the connection. The fallacy takes these forms:[11]

Events C and E both happened at the same time.
Therefore, C caused E.
    or     Events of type C have always been accompanied by events of type E.
Therefore, events of type C cause events of type E.

The fallacy is evident in arguments such as: The bigger a child's shoe size, the better the child's handwriting. Therefore, having big feet makes it easier to write. However, the fallacy is more insidious in statements such as:

Charging that welfare causes child poverty, [Gary Bauer] cites a study showing that "the highest increases in the rate of child poverty in recent years have occurred in those states which pay the highest welfare benefits. The lowest increases—or actual decreases—in child poverty have occurred in states which restrain the level of AFDC payments." — Source: John B. Judis, "The Mouse That Roars", The New Republic, August 3rd, 1987, p. 25.

Reversing Causation is an informal fallacy of false cause where cause and effect are reversed. The cause is said to be the effect and vice versa. Obvious examples of this fallacy include:

Hospitals are very dangerous; most people in hospitals are sick or injured.

Driving a wheelchair is dangerous, because most people who drive them have had an accident.

The faster windmills are observed to rotate, the more wind is observed to be.
Therefore wind is caused by the rotation of windmills.

In this last example, the correlation (simultaneity) between windmill activity and wind velocity does not imply that wind is caused by windmills. It is rather the other way around, as suggested by the fact that wind doesn’t need windmills to exist, while windmills need wind to rotate. Wind can be observed in places where there are no windmills or non-rotating windmills—and there are good reasons to believe that wind existed before the invention of windmills.

Arguments concluding that poverty causes crime or that crime causes poverty are an example of this fallacy unless clear evidence of the causality is provided. Arguing that:

  • Incarceration increases crime, or that crime increases incarceration rates,
  • Increases in inflation causes increases in unemployment, or that increases in unemployment causes increases in inflation,
  • Increases in gun ownership cause increases in gun violence, or increases in gun violence cause increases in gun ownership.
  • Rain causes the temperature to drop, or that a drop in temperature causes it to rain.

are additional examples of fallacies because no evidence of a causal link is provided.

Critics of supply-side economics describe it disparagingly as a trickle-down theory based on the idea that increasing income to the rich by reducing their taxes will reduce income inequality.

Begging the Question[edit]

It may be helpful to begin this section by viewing this Khan Academy video on Begging the Question.

Begging the question (in Latin petito principii “assuming the initial point”) is a form of circular reasoning in which a conclusion is derived from premises that presuppose the conclusion. In this fallacy the conclusion to be proven is used within a premise of the argument, often in an indirect way such that its presence within the premise is hidden or at least not easily apparent.

The fallacy takes the form: P therefore P.

The fallacy is present in any form of argument in which the conclusion occurs as one of the premises. This may be in the form of a chain of arguments in which the final conclusion is a premise of one of the earlier arguments in the chain.[12]

Here are some simple examples:

Whatever is less dense than water will float, because such objects won't sink in water.

Drink Rheingold extra dry, its beer as beer should taste.

Joe is not here because he does not go to parties.

I have a right to say what I want; therefore you shouldn’t try to silence me.

People have a right to exercise their first amendment rights.

Here are more consequential, pretentious, and real life examples:

“There's no greater argument for the existence of God than the truth of His existence.” —Robert T. Lee of the Society for the Practical Establishment and Perpetuation of the Ten Commandments.[13]

We know a god exists because we can see the perfect order of creation, an order which demonstrates supernatural intelligence in its design.[14]

Past-life memories of children prove that past lives exist because the children could have no other source for their memories besides having lived in the past.[15]

Accident and Converse Accident[edit]

Accident and Converse Accident—drawing hasty conclusions—are fallacies inferring that each member of a group shares the characteristics of the group, or that the group is characterized by the attributes of one particular member. These are the fallacies of stereotyping and non-representative samples.

An Accident fallacy is an unsound argument occurring when an exception to a rule of thumb is ignored. The fallacy occurs when a heuristic—a rule that is usually true—is mistaken for a categorical statement—a rule that is always true.

Other names for this fallacy include: destroying the exception, a dicto simpliciter ad dictum secundum quid, or simply a sweeping generalization.

The fallacy takes on the following form:

Xs are normally Ys.
A is an X. (Where A is not typical.)
Therefore, A is a Y.

Although penguins are birds, they do not fly.

For example:

Birds Fly.
Ping the Penguin is a bird.
Therefore, Ping can fly.

However, since Ping is a penguin and penguins don’t fly, the conclusion is invalid. The problem comes from ignoring (or misunderstanding) the exceptions to the generalization "birds fly" in this example. Now, it isn't true that all birds can fly, since there are flightless birds. "Some birds can fly" and "many birds can fly" are too weak, while "most birds can fly" is closer to what we mean. However, "birds can fly" is a "rule of thumb", that is, a rule that is generally true but has exceptions. The fallacy of accident in this sense occurs when attempting to apply such a rule to an obvious exception, such as concluding that a penguin can fly because penguins are birds and birds can fly.[16]

Discussions regarding rights often include fallacies of accident. For example, the First Amendment to the United States Constitution protects the right to free speech. However, the courts have ruled that this right is not absolute. For example, the Supreme Court generally refuses to give obscenity any protection under the First Amendment. As a result arguing that the right to free speech is protected, therefore I am free to shout an obscenity anytime and anywhere is a fallacy of accident.

One particular form of this fallacy is the toupée fallacy. It is most readily summed by the following phrase:

All toupées look fake; I've never seen one that I couldn't tell was fake.

It should be obvious that such a phrase can only be said about bad toupées—ones that look fake—and not all toupées. If the person uttering this phrase saw a convincing toupée, they wouldn't have noticed it at all. Hence it is a fallacy to draw such a conclusion from such a limited and biased evidence base.

The converse fallacy, called Converse Accident, occurs when an unrepresentative sample is used as the basis for too broad of a generalization.

Other names for this fallacy include: reverse accident, destroying the exception, a dicto secundum quid ad dictum simpliciter, or hasty generalization.

The fallacy takes on the following form:

X is a Y and has characteristic C
Therefore, all Y have characteristic C

For example

All the swans I have ever seen are white.
Therefore, all swans are white.

However, although many swans are white, black swans do exist, mainly in regions of Australia.

Other common examples include:

"Wow! Did you see that teenager run that red light? Teenage drivers are really pathetic."

Fat people are jolly. Joe is fat, so Joe must be jolly.

Early results lead to the hasty conclusion that lobotomy was safe and effective.

More tragically, reports of early success with the surgical procedure of lobotomy led to its widespread use as a mainstream procedure in some Western countries for more than two decades despite general recognition of frequent and serious side effects.


  1. Become alert for fallacies while listening to rhetoric, reading persuasive materials, or discussing and debating with others.
  2. Identify a specific instance of a fallacy of presumption in the arguments being presented.
  3. Name the specific fallacy of presumption that is being used.
  4. Identify the premise and the conclusion if they exist. Identify the evidence for each premise, if any. Cast that argument in the form of the specific fallacies of relevance studied here.
  5. Identify the missing information that would be required to make a valid argument. Recast the argument in a valid form, if possible.


  1. Copi, Irving M.; Cohen, Carl (June 20, 2001). Introduction to Logic. Prentice Hall. p. 647. ISBN 978-0130337351. Section 4.3 P1.
  5. Douglas E. Hill (2002). "Albright's Blunder". Irvine Review. Archived from the original on 2003-06-03. Retrieved 2008-01-04.
  6. Albright, Madeleine (2003). Madam Secretary: A Memoir. p. 275. ISBN 0-7868-6843-0.
  7. "Anti-smacking debate goes to referendum". 3 News. June 15, 2009. Retrieved 2010-02-03.
  9. The following is adapted with permission from