hypothesis contrary to fact logical fallacy

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Hypothesis Contrary To Fact

Imagine arguing about a reality that never happened, asserting cause and effect from a non-existent event, and presenting it as a fact - that's the intriguing world of this logical fallacy. It's like building castles in the air and then claiming they can actually house people, a captivating yet deceptive illusion that can mislead by creating a false sense of understanding or control over a situation.

• Cause and Effect
• Misrepresentation

Definition of Hypothesis Contrary To Fact 

Hypothesis Contrary To Fact, also known as "counterfactual fallacy" or "speculative fallacy," is a type of logical fallacy where a statement or argument is made based on a hypothetical situation that is presented as fact, but is actually contrary to what is known or proven to be true. This fallacy involves making a claim about a past event that didn't occur, and then asserting a cause and effect relationship based on that non-existent event. It is fallacious because it's impossible to definitively know the outcome of an event that did not happen. This fallacy can mislead or manipulate by creating an illusion of understanding or control over a situation, when in fact the hypothetical scenario and its supposed consequences are purely speculative. It's important to note that while hypothetical scenarios can be useful for exploring possibilities, they become fallacious when presented as factual or inevitable outcomes.

In Depth Explanation

The Hypothesis Contrary to Fact, also known as the Counterfactual Fallacy, is a logical error that occurs when an argument is built on a premise that is not true, but is presented as if it were. This fallacy involves making a claim about what would have happened in the past if a certain event had or hadn't occurred, even though there's no way to verify this claim because it's based on a hypothetical situation, not a factual one. Let's imagine a simple scenario to illustrate this fallacy. Suppose you're playing a game of chess and you lose. You then say, "If I had moved my queen instead of my pawn, I would have won the game." This statement is a hypothesis contrary to fact. You're making a claim about an alternate reality that didn't happen, and there's no way to prove whether your claim is true or false because we can't go back in time to see what would have happened if you had made a different move. The logical structure of this fallacy typically involves two statements: one that sets up a hypothetical situation ("If I had moved my queen...") and one that makes a claim about what would have happened in this situation ("...I would have won the game"). The problem is that the first statement is not true—you didn't move your queen—so any claim based on this statement is inherently flawed. This fallacy can be particularly misleading in abstract reasoning because it often sounds plausible. After all, it's easy to imagine how things might have turned out differently if we had made different choices. However, this kind of reasoning is purely speculative and doesn't provide a solid basis for an argument. The Hypothesis Contrary to Fact can have a significant impact on rational discourse because it can be used to deflect responsibility, justify poor decisions, or manipulate others. For example, a person might use this fallacy to argue that they would have succeeded if not for some external factor, thereby shifting the blame for their failure onto something beyond their control. Alternatively, a person might use this fallacy to convince others to take a certain course of action based on what they claim would have happened in a hypothetical situation. In conclusion, while it's natural to speculate about what might have been, it's important to recognize that these speculations are not facts and should not be treated as such in logical arguments. The Hypothesis Contrary to Fact is a fallacy that can lead us astray in our thinking and decision-making, so it's crucial to be aware of it and to challenge it when we encounter it.

Real World Examples

1. Sports Scenario: Imagine a basketball fan saying, "If Michael Jordan had not retired in 1993, the Chicago Bulls would have won eight consecutive NBA championships instead of six." This statement is an example of a hypothesis contrary to fact. It assumes a hypothetical scenario where Jordan didn't retire and then predicts an outcome based on that assumption. However, there's no way to prove this hypothesis because it's impossible to know how the Bulls would have performed had Jordan not retired. 2. Historical Event: A common example is the assertion, "If the United States had not entered World War II, the Allies would have lost." This is a hypothesis contrary to fact because it's based on a hypothetical scenario that didn't occur. While it's possible to speculate, there's no way to definitively know what would have happened had the U.S. not entered the war. 3. Everyday Scenario: Suppose a student who failed an exam says, "If I had just studied one more hour, I would have passed the test." This is an example of a hypothesis contrary to fact. The student is assuming that an extra hour of study would have made the difference between passing and failing, but there's no way to prove this. It's possible that the student might still have failed even with an additional hour of study, or they might have passed even without it. This statement is based on a hypothetical scenario, not on what actually happened.

Countermeasures

Addressing the logical fallacy of Hypothesis Contrary To Fact can be achieved through a few clear and concise steps. Firstly, it's important to encourage critical thinking. This involves questioning the basis of the hypothesis and examining the evidence that supports it. If the hypothesis is based on an event or circumstance that did not actually occur, it's crucial to point this out and discuss the implications of this. Secondly, promoting evidence-based reasoning is key. This means focusing on what we know to be true and what can be proven, rather than what might have been. If a hypothesis is based on a counterfactual, it's essential to redirect the conversation towards the facts at hand. Thirdly, fostering open-mindedness can help counteract this fallacy. This involves being open to alternative hypotheses and not being wedded to a particular outcome. It's important to be willing to change one's mind in the face of new evidence. Lastly, it's beneficial to cultivate a culture of intellectual humility. This means acknowledging the limits of our knowledge and being open to the possibility that we might be wrong. If a hypothesis is based on a counterfactual, it's important to acknowledge this and be willing to revise our views accordingly. In conclusion, countering the Hypothesis Contrary To Fact fallacy involves promoting critical thinking, evidence-based reasoning, open-mindedness, and intellectual humility. By fostering these qualities, we can help ensure that our hypotheses are grounded in fact, rather than in what might have been.

Thought Provoking Questions

1. Can you identify a time when you made a claim about a past event that didn't occur and asserted a cause and effect relationship based on that non-existent event? How did this impact your understanding or control over the situation? 2. Have you ever presented a hypothetical scenario as a factual or inevitable outcome? How did this affect your decision-making process and the decisions of those around you? 3. Can you recall a situation where you were misled by a 'Hypothesis Contrary To Fact' fallacy? How did this influence your perception of the situation and the actions you took? 4. How do you differentiate between useful hypothetical scenarios for exploring possibilities and those that are fallacious because they are presented as factual or inevitable outcomes? How has this skill affected your critical thinking and decision-making abilities?

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Counterfactual fallacy

A counterfactual fallacy occurs when someone states a fact, states that something would be true if the stated fact were not true, and provides no evidence for this position.

The fallacy is a causation fallacy and an informal fallacy .

• 1 Alternative names
• 2.1 Speculative evidence
• 3 Explanation
• 5 External links

Alternative names [ edit ]

• argumentum ad speculum
• hypothesis contrary to fact

Form [ edit ]

Or even more egregiously:

The second form doesn't even explain the causal connection between A and B; it really is just wild speculation. The first form is a special case of denying the antecedent , applied to counterfactual reasoning; it ignores the possibility of B still occurring as an effect of causes other than A, even if A had not occurred.

Speculative evidence [ edit ]

You commit this fallacy if you draw conclusions from evidence that hasn't been collected yet, but that, one supposes, would have come out in favor of one's own opinion.

If there is no evidence to support a particular point, do not rely on that point to carry your argument. If pressed on a point where there is not valid evidence to support it, acknowledge the lack of data and suggest that the matter needs to be investigated in order to resolve the disputed issue.

Explanation [ edit ]

Confusing "what might have been" with "what ought to have been"; speculating what would have happened in other circumstances, then drawing conclusions from the speculation.

Examples [ edit ]

• "We'd never have all this crime if [X] was president." This is unknowable because [X] isn't president.
• "In this country citizens are permitted to own guns . If guns were outlawed, citizens would be unable to protect themselves and there would be an uncontrollable crime wave."

External links [ edit ]

• See the Wikipedia article on Counterfactual conditional .
• Hypothesis Contrary to Fact , Logically Fallacious
• Logical Fallacy of Hypothesis Contrary to Fact , SeekFind
• Counterfactuals (PDF) , Richard Holton
• Counterfactuals , OneGoodMove
• Hypothesis Contrary to Fact , Robert Gass
• Hypothesis Contrary to Fact , DAVID PETERSON
• Speculative Evidence , Bruce Thompson
• ↑ https://www2.palomar.edu/users/bthompson/Hypothesis%20Contrary%20to%20Fact.html
• Causation fallacies
• Informal fallacies
• Latin phrases
• Pages using DynamicPageList parser function

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Structure & Outlining

Logical fallacies handlist.

Logical Fallacies Handlist: Fallacies are statements that might sound reasonable or superficially true but are actually flawed or dishonest. When readers detect them, these logical fallacies backfire by making the audience think the writer is (a) unintelligent or (b) deceptive. It is important to avoid them in your own arguments, and it is also important to be able to spot them in others’ arguments so a false line of reasoning won’t fool you. Think of this as intellectual kung-fu : the vital art of self-defense in a debate. For extra impact, learn both the Latin terms and the English equivalents. You can click here to download a PDF version of this material . In general, one useful way to organize fallacies is by category. We have below fallacies of relevance , component fallacies , fallacies of ambiguity , and fallacies of omission . We will discuss each type in turn. The last point to discuss is Occam’s Razor . FALLACIES OF RELEVANCE : These fallacies appeal to evidence or examples that are not relevant to the argument at hand. Appeal to Force ( Argumentum Ad Baculum or the “Might-Makes-Right” Fallacy): This argument uses force, the threat of force, or some other unpleasant backlash to make the audience accept a conclusion. It commonly appears as a last resort when evidence or rational arguments fail to convince a reader. If the debate is about whether or not 2+2=4, an opponent’s argument that he will smash your nose in if you don’t agree with his claim doesn’t change the truth of an issue. Logically, this consideration has nothing to do with the points under consideration. The fallacy is not limited to threats of violence, however. The fallacy includes threats of any unpleasant backlash–financial, professional, and so on. Example: “Superintendent, you should cut the school budget by $16,000. I need not remind you that past school boards have fired superintendents who cannot keep down costs.” While intimidation may force the superintendent to conform, it does not convince him that the choice to cut the budget was the most beneficial for the school or community. Lobbyists use this method when they remind legislators that they represent so many thousand votes in the legislators’ constituencies and threaten to throw the politician out of office if he doesn’t vote the way they want. Teachers use this method if they state that students should hold the same political or philosophical position as the teachers or risk failing the class. Note that it is isn’t a logical fallacy, however, to assert that students must fulfill certain requirements in the course or risk failing the class! Genetic Fallacy : The genetic fallacy is the claim that an idea, product, or person must be untrustworthy because of its racial, geographic, or ethnic origin. “That car can’t possibly be any good! It was made in Japan!” Or, “Why should I listen to her argument? She comes from California, and we all know those people are flakes.” Or, “Ha! I’m not reading that book. It was published in Tennessee, and we know all Tennessee folk are hillbillies and rednecks!” This type of fallacy is closely related to the fallacy of argumentum ad hominem or personal attack , appearing immediately below. Personal Attack ( Argumentum Ad Hominem , literally, “argument toward the man.” Also called “Poisoning the Well”): Attacking or praising the people who make an argument, rather than discussing the argument itself. This practice is fallacious because the personal character of an individual is logically irrelevant to the truth or falseness of the argument itself. The statement “2+2=4” is true regardless if it is stated by criminals, congressmen, or pastors. There are two subcategories: (1) Abusive : To argue that proposals, assertions, or arguments must be false or dangerous because they originate with atheists, Christians, Muslims, communists, capitalists, the John Birch Society, Catholics, anti-Catholics, racists, anti-racists, feminists, misogynists (or any other group) is fallacious. This persuasion comes from irrational psychological transference rather than from an appeal to evidence or logic concerning the issue at hand. This is similar to the genetic fallacy , and only an anti-intellectual would argue otherwise.

(2) Circumstantial : To argue that an opponent should accept or reject an argument because of circumstances in his or her life. If one’s adversary is a clergyman, suggesting that he should accept a particular argument because not to do so would be incompatible with the scriptures is such a fallacy. To argue that, because the reader is a Republican or Democrat, she must vote for a specific measure is likewise a circumstantial fallacy. The opponent’s special circumstances have no control over the truth or untruth of a specific contention. The speaker or writer must find additional evidence beyond that to make a strong case. This is also similar to the genetic fallacy in some ways. If you are a college student who wants to learn rational thought, you simply must avoid circumstantial fallacies.

Argumentum ad Populum (Literally “Argument to the People”): Using an appeal to popular assent, often by arousing the feelings and enthusiasm of the multitude rather than building an argument. It is a favorite device with the propagandist, the demagogue, and the advertiser. An example of this type of argument is Shakespeare’s version of Mark Antony’s funeral oration for Julius Caesar. There are three basic approaches:

(1) Bandwagon Approach : “Everybody is doing it.” This argumentum ad populum asserts that, since the majority of people believes an argument or chooses a particular course of action, the argument must be true, or the course of action must be followed, or the decision must be the best choice. For instance, “85% of consumers purchase IBM computers rather than Macintosh; all those people can’t be wrong. IBM must make the best computers.” Popular acceptance of any argument does not prove it to be valid, nor does popular use of any product necessarily prove it is the best one. After all, 85% of people may once have thought planet earth was flat, but that majority’s belief didn’t mean the earth really was flat when they believed it! Keep this in mind, and remember that everybody should avoid this type of logical fallacy.

(2) Patriotic Approach : “Draping oneself in the flag.” This argument asserts that a certain stance is true or correct because it is somehow patriotic, and that those who disagree are unpatriotic. It overlaps with pathos and argumentum ad hominem to a certain extent. The best way to spot it is to look for emotionally charged terms like Americanism, rugged individualism, motherhood, patriotism, godless communism, etc. A true American would never use this approach. And a truly free man will exercise his American right to drink beer, since beer belongs in this great country of ours. This approach is unworthy of a good citizen. (3) Snob Approach : This type of argumentum ad populum doesn’t assert “everybody is doing it,” but rather that “all the best people are doing it.” For instance, “Any true intellectual would recognize the necessity for studying logical fallacies.” The implication is that anyone who fails to recognize the truth of the author’s assertion is not an intellectual, and thus the reader had best recognize that necessity.

In all three of these examples, the rhetorician does not supply evidence that an argument is true; he merely makes assertions about people who agree or disagree with the argument. For Christian students in religious schools like Carson-Newman, we might add a fourth category, “ Covering Oneself in the Cross .” This argument asserts that a certain political or denominational stance is true or correct because it is somehow “Christian,” and that anyone who disagrees is behaving in an “un-Christian” or “godless” manner. (It is similar to the patriotic approach except it substitutes a gloss of piety instead of patriotism.) Examples include the various “Christian Voting Guides” that appear near election time, many of them published by non-Church related organizations with hidden financial/political agendas, or the stereotypical crooked used-car salesman who keeps a pair of bibles on his dashboard in order to win the trust of those he would fleece. Keep in mind Moliere’s question in Tartuffe : “Is not a face quite different than a mask?” Is not the appearance of Christianity quite different than actual Christianity? Christians should beware of such manipulation since they are especially vulnerable to it.

Appeal to Tradition ( Argumentum Ad Traditionem; aka Argumentum Ad Antiquitatem ): This line of thought asserts that a premise must be true because people have always believed it or done it. For example, “We know the earth is flat because generations have thought that for centuries!” Alternatively, the appeal to tradition might conclude that the premise has always worked in the past and will thus always work in the future: “Jefferson City has kept its urban growth boundary at six miles for the past thirty years. That has been good enough for thirty years, so why should we change it now? If it ain’t broke, don’t fix it.” Such an argument is appealing in that it seems to be common sense, but it ignores important questions. Might an alternative policy work even better than the old one? Are there drawbacks to that long-standing policy? Are circumstances changing from the way they were thirty years ago? Has new evidence emerged that might throw that long-standing policy into doubt?

Appeal to Improper Authority ( Argumentum Ad Verecundium, literally “argument from that which is improper”): An appeal to an improper authority, such as a famous person or a source that may not be reliable or who might not know anything about the topic. This fallacy attempts to capitalize upon feelings of respect or familiarity with a famous individual. It is not fallacious to refer to an admitted authority if the individual’s expertise is within a strict field of knowledge. On the other hand, to cite Einstein to settle an argument about education or economics is fallacious. To cite Darwin, an authority on biology, on religious matters is fallacious. To cite Cardinal Spellman on legal problems is fallacious. The worst offenders usually involve movie stars and psychic hotlines. A subcategory is the Appeal to Biased Authority . In this sort of appeal, the authority is one who actually is knowledgeable on the matter, but one who may have professional or personal motivations that render his professional judgment suspect: for instance, “To determine whether fraternities are beneficial to this campus, we interviewed all the frat presidents.” Or again, “To find out whether or not sludge-mining really is endangering the Tuskogee salamander’s breeding grounds, we interviewed the owners of the sludge-mines, who declared there is no problem.” Indeed, it is important to get “both viewpoints” on an argument, but basing a substantial part of your argument on a source that has personal, professional, or financial interests at stake may lead to biased arguments. As Upton Sinclair once stated, “It’s difficult to get a man to understand something when his salary depends upon his not understanding it.” Sinclair is pointing out that even a knowledgeable authority might not be entirely rational on a topic when he has economic incentives that bias his thinking.

Appeal to Emotion (Argumentum Ad Misericordiam , literally, “argument from pity”): An emotional appeal concerning what should be a logical issue during a debate. While pathos generally works to reinforce a reader’s sense of duty or outrage at some abuse, if a writer tries to use emotion merely for the sake of getting the reader to accept what should be a logical conclusion, the argument is a fallacy. For example, in the 1880s, prosecutors in a Virginia court presented overwhelming proof that a boy was guilty of murdering his parents with an ax. The defense presented a “not-guilty” plea for on the grounds that the boy was now an orphan, with no one to look after his interests if the court was not lenient. This appeal to emotion obviously seems misplaced, and the argument is irrelevant to the question of whether or not he did the crime.

Argument from Adverse Consequences: Asserting that an argument must be false because the implications of it being true would create negative results. For instance, “The medical tests show that Grandma has advanced cancer. However, that can’t be true because then she would die! I refuse to believe it!”  The argument is illogical because truth and falsity are not contingent based upon how much we like or dislike the consequences of that truth. Grandma, indeed, might have cancer, in spite of how negative that fact may be or how cruelly it may affect us.

Argument from Personal Incredulity : Asserting that opponent’s argument must be false because you personally don’t understand it or can’t follow its technicalities. For instance, one person might assert, “I don’t understand that engineer’s argument about how airplanes can fly. Therefore, I cannot believe that airplanes are able to fly.” Au contraire , that speaker’s own mental limitations do not limit the physical world—so airplanes may very well be able to fly in spite of a person’s inability to understand how they work. One person’s comprehension is not relevant to the truth of a matter.

Begging the Question (also called Petitio Principii , this term is sometimes used interchangeably with Circular Reasoning ): If writers assume as evidence for their argument the very conclusion they are attempting to prove, they engage in the fallacy of begging the question. The most common form of this fallacy is when the first claim is initially loaded with the very conclusion one has yet to prove. For instance, suppose a particular student group states, “Useless courses like English 101 should be dropped from the college’s curriculum.” The members of the student group then immediately move on in the argument, illustrating that spending money on a useless course is something nobody wants. Yes, we all agree that spending money on useless courses is a bad thing. However, those students never did prove that English 101 was itself a useless course–they merely “begged the question” and moved on to the next “safe” part of the argument, skipping over the part that’s the real controversy, the heart of the matter, the most important component. Begging the question is often hidden in the form of a complex question (see below).

Circular Reasoning is closely related to begging the question . Often the writers using this fallacy word take one idea and phrase it in two statements. The assertions differ sufficiently to obscure the fact that that the same proposition occurs as both a premise and a conclusion. The speaker or author then tries to “prove” his or her assertion by merely repeating it in different words. Richard Whately wrote in Elements of Logic (London 1826): “To allow every man unbounded freedom of speech must always be on the whole, advantageous to the state; for it is highly conducive to the interest of the community that each individual should enjoy a liberty perfectly unlimited of expressing his sentiments.” Obviously the premise is not logically irrelevant to the conclusion, for if the premise is true the conclusion must also be true. It is, however, logically irrelevant in proving the conclusion. In the example, the author is repeating the same point in different words, and then attempting to “prove” the first assertion with the second one. A more complex but equally fallacious type of circular reasoning is to create a circular chain of reasoning like this one: “God exists.” “How do you know that God exists?” “The Bible says so.” “Why should I believe the Bible?” “Because it’s the inspired word of God.” If we draw this out as a chart, it looks like this:

The so-called “final proof” relies on unproven evidence set forth initially as the subject of debate. Basically, the argument goes in an endless circle, with each step of the argument relying on a previous one, which in turn relies on the first argument yet to be proven. Surely God deserves a more intelligible argument than the circular reasoning proposed in this example!

Hasty Generalization ( Dicto Simpliciter , also called “Jumping to Conclusions,” “Converse Accident”): Mistaken use of inductive reasoning when there are too few samples to prove a point. Example: “Susan failed Biology 101. Herman failed Biology 101. Egbert failed Biology 101. I therefore conclude that most students who take Biology 101 will fail it.” In understanding and characterizing general situations, a logician cannot normally examine every single example. However, the examples used in inductive reasoning should be typical of the problem or situation at hand. Maybe Susan, Herman, and Egbert are exceptionally poor students. Maybe they were sick and missed too many lectures that term to pass. If a logician wants to make the case that most students will fail Biology 101, she should (a) get a very large sample–at least one larger than three–or (b) if that isn’t possible, she will need to go out of his way to prove to the reader that her three samples are somehow representative of the norm. If a logician considers only exceptional or dramatic cases and generalizes a rule that fits these alone, the author commits the fallacy of hasty generalization.

One common type of hasty generalization is the Fallacy of Accident . This error occurs when one applies a general rule to a particular case when accidental circumstances render the general rule inapplicable. For example, in Plato’s Republic , Plato finds an exception to the general rule that one should return what one has borrowed: “Suppose that a friend when in his right mind has deposited arms with me and asks for them when he is not in his right mind. Ought I to give the weapons back to him? No one would say that I ought or that I should be right in doing so. . . .” What is true in general may not be true universally and without qualification. So remember, generalizations are bad. All of them. Every single last one. Except, of course, for those that are not.

Another common example of this fallacy is the misleading statistic . Suppose an individual argues that women must be incompetent drivers, and he points out that last Tuesday at the Department of Motor Vehicles, 50% of the women who took the driving test failed. That would seem to be compelling evidence from the way the statistic is set forth. However, if only two women took the test that day, the results would be far less clear-cut. Incidentally, the cartoon Dilbert makes much of an incompetent manager who cannot perceive misleading statistics. He does a statistical study of when employees call in sick and cannot come to work during the five-day work week. He becomes furious to learn that 40% of office “sick-days” occur on Mondays (20%) and Fridays (20%)–just in time to create a three-day weekend. Suspecting fraud, he decides to punish his workers. The irony, of course, is that these two days compose 40% of a five day work week, so the numbers are completely average. Similar nonsense emerges when parents or teachers complain that “50% of students perform at or below the national average on standardized tests in mathematics and verbal aptitude.” Of course they do! The very nature of an average implies that!

False Cause : This fallacy establishes a cause/effect relationship that does not exist. There are various Latin names for various analyses of the fallacy. The two most common include these types:

(1) Non Causa Pro Causa (Literally, “Not the cause for a cause”): A general, catch-all category for mistaking a false cause of an event for the real cause. (2) Post Hoc, Ergo Propter Hoc (Literally: “After this, therefore because of this”): This type of false cause occurs when the writer mistakenly assumes that, because the first event preceded the second event, it must mean the first event caused the later one. Sometimes it does, but sometimes it doesn’t. It is the honest writer’s job to establish clearly that connection rather than merely assert it exists. Example: “A black cat crossed my path at noon. An hour later, my mother had a heart-attack. Because the first event occurred earlier, it must have caused the bad luck later.” This is how superstitions begin. The most common examples are arguments that viewing a particular movie or show, or listening to a particular type of music “caused” the listener to perform an antisocial act–to snort coke, shoot classmates, or take up a life of crime. These may be potential suspects for the cause, but the mere fact that an individual did these acts and subsequently behaved in a certain way does not yet conclusively rule out other causes. Perhaps the listener had an abusive home-life or school-life, suffered from a chemical imbalance leading to depression and paranoia, or made a bad choice in his companions. Other potential causes must be examined before asserting that only one event or circumstance alone earlier in time caused a event or behavior later. For more information, see correlation and causation .

Irrelevant Conclusion ( Ignorantio Elenchi ): This fallacy occurs when a rhetorician adapts an argument purporting to establish a particular conclusion and directs it to prove a different conclusion. For example, when a particular proposal for housing legislation is under consideration, a legislator may argue that decent housing for all people is desirable. Everyone, presumably, will agree. However, the question at hand concerns a particular measure. The question really isn’t, “Is it good to have decent housing?” The question really is, “Will this particular measure actually provide it or is there a better alternative?” This type of fallacy is a common one in student papers when students use a shared assumption–such as the fact that decent housing is a desirable thing to have–and then spend the bulk of their essays focused on that fact rather than the real question at issue. It’s similar to begging the question , above.

One of the most common forms of Ignorantio Elenchi is the “ Red Herring .” A red herring is a deliberate attempt to change the subject or divert the argument from the real question at issue to some side-point; for instance, “Senator Jones should not be held accountable for cheating on his income tax. After all, there are other senators who have done far worse things.” Another example: “I should not pay a fine for reckless driving. There are many other people on the street who are dangerous criminals and rapists, and the police should be chasing them, not harassing a decent tax-paying citizen like me.” Certainly, worse criminals do exist, but that it is another issue! The questions at hand are (1) did the speaker drive recklessly, and (2) should he pay a fine for it?

Another similar example of the red herring is the fallacy known as Tu Quoque (Latin for “And you too!”), which asserts that the advice or argument must be false simply because the person presenting the advice doesn’t consistently follow it herself. For instance, “Susan the yoga instructor claims that a low-fat diet and exercise are good for you–but I saw her last week pigging out on oreos, so her argument must be a load of hogwash.” Or, “Reverend Jeremias claims that theft is wrong, but how can theft be wrong if Jeremias himself admits he stole objects when he was a child?” Or “Thomas Jefferson made many arguments about equality and liberty for all Americans, but he himself kept slaves, so we can dismiss any thoughts he had on those topics.”

Straw Man Argument : A subtype of the red herring , this fallacy includes any lame attempt to “prove” an argument by overstating, exaggerating, or over-simplifying the arguments of the opposing side. Such an approach is building a straw man argument. The name comes from the idea of a boxer or fighter who meticulously fashions a false opponent out of straw, like a scarecrow, and then easily knocks it over in the ring before his admiring audience. His “victory” is a hollow mockery, of course, because the straw-stuffed opponent is incapable of fighting back. When a writer makes a cartoon-like caricature of the opposing argument, ignoring the real or subtle points of contention, and then proceeds to knock down each “fake” point one-by-one, he has created a straw man argument.

For instance, one speaker might be engaged in a debate concerning welfare. The opponent argues, “Tennessee should increase funding to unemployed single mothers during the first year after childbirth because they need sufficient money to provide medical care for their newborn children.” The second speaker retorts, “My opponent believes that some parasites who don’t work should get a free ride from the tax money of hard-working honest citizens. I’ll show you why he’s wrong . . .” In this example, the second speaker is engaging in a straw man strategy, distorting the opposition’s statement about medical care for newborn children into an oversimplified form so he can more easily appear to “win.” However, the second speaker is only defeating a dummy-argument rather than honestly engaging in the real nuances of the debate.

Non Sequitur (literally, “It does not follow”): A non sequitur is any argument that does not follow from the previous statements. Usually what happened is that the writer leaped from A to B and then jumped to D, leaving out step C of an argument she thought through in her head, but did not put down on paper. The phrase is applicable in general to any type of logical fallacy, but logicians use the term particularly in reference to syllogistic errors such as the undistributed middle term , non causa pro causa , and ignorantio elenchi . A common example would be an argument along these lines: “Giving up our nuclear arsenal in the 1980’s weakened the United States’ military. Giving up nuclear weaponry also weakened China in the 1990s. For this reason, it is wrong to try to outlaw pistols and rifles in the United States today.” There’s obviously a step or two missing here.

The “Slippery Slope” Fallacy (also called “The Camel’s Nose Fallacy”) is a non sequitur in which the speaker argues that, once the first step is undertaken, a second or third step will inevitably follow, much like the way one step on a slippery incline will cause a person to fall and slide all the way to the bottom. It is also called “the Camel’s Nose Fallacy” because of the image of a sheik who let his camel stick its nose into his tent on a cold night. The idea is that the sheik is afraid to let the camel stick its nose into the tent because once the beast sticks in its nose, it will inevitably stick in its head, and then its neck, and eventually its whole body. However, this sort of thinking does not allow for any possibility of stopping the process. It simply assumes that, once the nose is in, the rest must follow–that the sheik can’t stop the progression once it has begun–and thus the argument is a logical fallacy. For instance, if one were to argue, “If we allow the government to infringe upon our right to privacy on the Internet, it will then feel free to infringe upon our privacy on the telephone. After that, FBI agents will be reading our mail. Then they will be placing cameras in our houses. We must not let any governmental agency interfere with our Internet communications, or privacy will completely vanish in the United States.” Such thinking is fallacious; no logical proof has been provided yet that infringement in one area will necessarily lead to infringement in another, no more than a person buying a single can of Coca-Cola in a grocery store would indicate the person will inevitably go on to buy every item available in the store, helpless to stop herself. So remember to avoid the slippery slope fallacy; once you use one, you may find yourself using more and more logical fallacies.

Either/Or Fallacy (also called “the Black-and-White Fallacy,” “Excluded Middle,” “False Dilemma,” or “False Dichotomy”): This fallacy occurs when a writer builds an argument upon the assumption that there are only two choices or possible outcomes when actually there are several. Outcomes are seldom so simple. This fallacy most frequently appears in connection to sweeping generalizations: “Either we must ban X or the American way of life will collapse.” “We go to war with Canada, or else Canada will eventually grow in population and overwhelm the United States.” “Either you drink Burpsy Cola, or you will have no friends and no social life.” Either you must avoid either/or fallacies, or everyone will think you are foolish.

Faulty Analogy : Relying only on comparisons to prove a point rather than arguing deductively and inductively. For example, “education is like cake; a small amount tastes sweet, but eat too much and your teeth will rot out. Likewise, more than two years of education is bad for a student.” The analogy is only acceptable to the degree a reader thinks that education is similar to cake. As you can see, faulty analogies are like flimsy wood, and just as no carpenter would build a house out of flimsy wood, no writer should ever construct an argument out of flimsy material.

Undistributed Middle Term : A specific type of error in deductive reasoning in which the minor premise and the major premise of a syllogism might or might not overlap. Consider these two examples: (1) “All reptiles are cold-blooded. All snakes are reptiles. All snakes are cold-blooded.” In the first example, the middle term “snakes” fits in the categories of both “reptile” and “things-that-are-cold-blooded.” (2) “All snails are cold-blooded. All snakes are cold-blooded. All snails are snakes.” In the second example, the middle term of “snakes” does not fit into the categories of both “things-that-are-cold-blooded” and “snails.” Sometimes, equivocation (see below) leads to an undistributed middle term.

Contradictory Premises (also known as a logical paradox): Establishing a premise in such a way that it contradicts another, earlier premise. For instance, “If God can do anything, he can make a stone so heavy that he can’t lift it.” The first premise establishes a deity that has the irresistible capacity to move other objects. The second premise establishes an immovable object impervious to any movement. If the first object capable of moving anything exists, by definition, the immovable object cannot exist, and vice-versa .

Closely related is the fallacy of Special Pleading , in which the writer creates a universal principle, then insists that principle does not for some reason apply to the issue at hand. For instance, “Everything must have a source or creator. Therefore God must exist and he must have created the world. What? Who created God? Well, God is eternal and unchanging–He has no source or creator.” In such an assertion, either God must have His own source or creator, or else the universal principle of everything having a source or creator must be set aside—the person making the argument can’t have it both ways.

FALLACIES OF AMBIGUITY : These errors occur with ambiguous words or phrases, the meanings of which shift and change in the course of discussion. Such more or less subtle changes can render arguments fallacious.

Equivocation : Using a word in a different way than the author used it in the original premise, or changing definitions halfway through a discussion. When we use the same word or phrase in different senses within one line of argument, we commit the fallacy of equivocation. Consider this example: “Plato says the end of a thing is its perfection; I say that death is the end of life; hence, death is the perfection of life.” Here the word end means “goal” in Plato’s usage, but it means “last event” or “termination” in the author’s second usage. Clearly, the speaker is twisting Plato’s meaning of the word to draw a very different conclusion. Compare with amphiboly , below.

Amphiboly (from the Greek word “indeterminate”): This fallacy is similar to equivocation. Here, the ambiguity results from grammatical construction. A statement may be true according to one interpretation of how each word functions in a sentence and false according to another. When a premise works with an interpretation that is true, but the conclusion uses the secondary “false” interpretation, we have the fallacy of amphiboly on our hands. In the command, “Save soap and waste paper,” the amphibolous use of “waste” results in the problem of determining whether “waste” functions as a verb or as an adjective.

Composition : This fallacy is a result of reasoning from the properties of the parts of the whole to the properties of the whole itself–it is an inductive error. Such an argument might hold that, because every individual part of a large tractor is lightweight, the entire machine also must be lightweight. This fallacy is similar to Hasty Generalization (see above), but it focuses on parts of a single whole rather than using too few examples to create a categorical generalization. Also compare it with Division (see below).

Division : This fallacy is the reverse of composition . It is the misapplication of deductive reasoning. One fallacy of division argues falsely that what is true of the whole must be true of individual parts. Such an argument notes that, “Microtech is a company with great influence in the California legislature. Egbert Smith works at Microtech. He must have great influence in the California legislature.” This is not necessarily true. Egbert might work as a graveyard shift security guard or as the copy-machine repairman at Microtech–positions requiring little interaction with the California legislature. Another fallacy of division attributes the properties of the whole to the individual member of the whole: “Sunsurf is a company that sells environmentally safe products. Susan Jones is a worker at Sunsurf. She must be an environmentally minded individual.” (Perhaps she is motivated by money alone?)

Fallacy of Reification (Also called “ Fallacy of Misplaced Concreteness ” by Alfred North Whitehead): The fallacy of treating a word or an idea as equivalent to the actual thing represented by that word or idea, or the fallacy of treating an abstraction or process as equivalent to a concrete object or thing.  In the first case, we might imagine a reformer trying to eliminate illicit lust by banning all mention of extra-marital affairs or certain sexual acts in publications. The problem is that eliminating the words for these deeds is not the same as eliminating the deeds themselves. In the second case, we might imagine a person or declaring “a war on poverty.” In this case, the fallacy comes from the fact that “war” implies a concrete struggle with another concrete entity which can surrender or be exterminated. “Poverty,” however is an abstraction that cannot surrender or sign peace treaties, cannot be shot or bombed, etc. Reification of the concept merely muddles the issue of what policies to follow and leads to sloppy thinking about the best way to handle a problem. It is closely related to and overlaps with faulty analogy and equivocation .

FALLACIES O F OMISSION : These errors occur because the logician leaves out necessary material in an argument or misdirects others from missing information.

Stacking the Deck : In this fallacy, the speaker “stacks the deck” in her favor by ignoring examples that disprove the point and listing only those examples that support her case. This fallacy is closely related to hasty generalization, but the term usually implies deliberate deception rather than an accidental logical error. Contrast it with the straw man argument .

‘No True Scotsman’ Fallacy : Attempting to stack the deck specifically by defining terms in such a narrow or unrealistic manner as to exclude or omit relevant examples from a sample. For instance, suppose speaker #1 asserts, “The Scottish national character is brave and patriotic. No Scottish soldier has ever fled the field of battle in the face of the enemy.” Speaker #2 objects, “Ah, but what about Lucas MacDurgan? He fled from German troops in World War I.” Speaker #1 retorts, “Well, obviously he doesn’t count as a true Scotsman because he did not live up to Scottish ideals, thus he forfeited his Scottish identity.” By this fallacious reasoning, any individual who would serve as evidence contradicting the first speaker’s assertion is conveniently and automatically dismissed from consideration. We commonly see this fallacy when a company asserts that it cannot be blamed for one of its particularly unsafe or shoddy products because that particular one doesn’t live up to its normally high standards, and thus shouldn’t “count” against its fine reputation. Likewise, defenders of Christianity as a positive historical influence in their zeal might argue the atrocities of the eight Crusades do not “count” in an argument because the Crusaders weren’t living up to Christian ideals, and thus aren’t really Christians, etc. So, remember this fallacy. Philosophers and logicians never use it, and anyone who does use it by definition is not really a philosopher or logician.

Argument from the Negative : Arguing from the negative asserts that, since one position is untenable, the opposite stance must be true. This fallacy is often used interchangeably with Argumentum Ad Ignorantium (listed below) and the either/or fallacy (listed above). For instance, one might mistakenly argue that, since the Newtonian theory of mathematics is not one hundred percent accurate, Einstein’s theory of relativity must be true. Perhaps not. Perhaps the theories of quantum mechanics are more accurate, and Einstein’s theory is flawed. Perhaps they are all wrong. Disproving an opponent’s argument does not necessarily mean your own argument must be true automatically, no more than disproving your opponent’s assertion that 2+2=5 would automatically mean your argument that 2+2=7 must be the correct one. Keeping this mind, students should remember that arguments from the negative are bad, arguments from the positive must automatically be good.

Appeal to a Lack of Evidence ( Argumentum Ad Ignorantium , literally “Argument from Ignorance”): Appealing to a lack of information to prove a point, or arguing that, since the opposition cannot disprove a claim, the opposite stance must be true. An example of such an argument is the assertion that ghosts must exist because no one has been able to prove that they do not exist. Logicians know this is a logical fallacy because no competing argument has yet revealed itself.

Hypothesis Contrary to Fact ( Argumentum Ad Speculum ): Trying to prove something in the real world by using imaginary examples alone, or asserting that, if hypothetically X had occurred, Y would have been the result. For instance, suppose an individual asserts that if Einstein had been aborted in utero , the world would never have learned about relativity, or that if Monet had been trained as a butcher rather than going to college, the impressionistic movement would have never influenced modern art. Such hypotheses are misleading lines of argument because it is often possible that some other individual would have solved the relativistic equations or introduced an impressionistic art style. The speculation might make an interesting thought-experiment, but it is simply useless when it comes to actually proving anything about the real world. A common example is the idea that one “owes” her success to another individual who taught her. For instance, “You owe me part of your increased salary. If I hadn’t taught you how to recognize logical fallacies, you would be flipping hamburgers at McDonald’s for minimum wages right now instead of taking in hundreds of thousands of dollars as a lawyer.” Perhaps. But perhaps the audience would have learned about logical fallacies elsewhere, so the hypothetical situation described is meaningless.

Complex Question (Also called the “Loaded Question”): Phrasing a question or statement in such as way as to imply another unproven statement is true without evidence or discussion. This fallacy often overlaps with begging the question (above), since it also presupposes a definite answer to a previous, unstated question. For instance, if I were to ask you “Have you stopped taking drugs yet?” my hidden supposition is that you have been taking drugs. Such a question cannot be answered with a simple yes or no answer. It is not a simple question but consists of several questions rolled into one. In this case the unstated question is, “Have you taken drugs in the past?” followed by, “If you have taken drugs in the past, have you stopped taking them now?” In cross-examination, a lawyer might ask a flustered witness, “Where did you hide the evidence?” or “when did you stop beating your wife?” The intelligent procedure when faced with such a question is to analyze its component parts. If one answers or discusses the prior, implicit question first, the explicit question may dissolve.

Complex questions appear in written argument frequently. A student might write, “Why is private development of resources so much more efficient than any public control?” The rhetorical question leads directly into his next argument. However, an observant reader may disagree, recognizing the prior, implicit question remains unaddressed. That question is, of course, whether private development of resources really is more efficient in all cases, a point which the author is skipping entirely and merely assuming to be true without discussion.

To master logic more fully, become familiar with the tool of Occam’s Razor .

Candela Citations

• Logical Fallacies Handlist. Authored by : Dr. Kip Wheeler. Provided by : Carson Newman University. Located at : https://web.cn.edu/kwheeler/fallacies_list.html . License : CC BY-SA: Attribution-ShareAlike

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A logical fallacy occurs when someone tries to persuade you with a faulty argument. Sometimes, logical fallacies are innocuous: the writer has a good argument to make, it was just set up through faulty logic. However, logical fallacies run rampant among less-than-sincere writers, and if you want to write well and read well, then knowing our list of logical fallacies will help arm you against faulty arguments.

Because people are constantly trying to persuade you of something—politicians, advertisers, social media posts, etc.—logical fallacies occur all the time. Good persuasive writers will know how to avoid these common logical fallacies, and good readers will know how to identify them without being persuaded.

So, what is a logical fallacy? And why do they matter for my writing? Understanding the arguments in this list of logical fallacies will help strengthen your writing and ability to write effective arguments. But before we look at some examples of logical fallacies, let’s get clear on these persuasive and invasive mistakes in rhetoric.

Logical Fallacy Definition: What is a Logical Fallacy?

Common types of logical fallacies, a note on good persuasive writing, logical fallacies examples: fallacies of relevance, logical fallacies examples: fallacies of unacceptable premises, logical fallacies examples: formal fallacies, other logical fallacies examples.

Simply put, a logical fallacy is an error in reasoning that undermines the logic of an argument. It does not necessarily undermine the persuasiveness of that argument, however; unless you are well-versed in the different types of logical fallacies, you can certainly be persuaded by one yourself.

A logical fallacy is an error in reasoning that undermines the logic, but not necessarily the persuasiveness, of an argument.

A common logical fallacy example is a red herring. A red herring is an attempt to divert the audience’s attention from the argument itself. It might look something like this:

Some people criticize the SAT for measuring test taking skills, not college readiness. Nonetheless, a high SAT score will get you into better colleges.

This statement isn’t actually addressing the issue of the SAT’s validity, it’s distracting you by bringing up the importance of a high test score, going so far as dismissing the original claim entirely.

All logical fallacies have one thing in common: they don’t hold up to scrutiny. But there are different ways in which writers might present less-than-foolproof arguments. Let’s examine the common types of logical fallacies.

All logical fallacies have one thing in common: they don’t hold up to scrutiny.

Most logical fallacies can be sorted into one of three categories:

• For example: You had a bad day because Mercury is in retrograde.
• For example: You had a bad day because you always have bad days when it rains before noon. 
• For example: Because rain symbolizes sadness , and because you are having a bad day, the rain is causing your bad day. 
• In a formal fallacy, the flaw is in the logic and conclusion. Most other fallacies are informal fallacies, in which the flaw is simply the logic.

We’ll examine these three categories shortly. But before we examine some examples of logical fallacies, let’s talk about good persuasive writing.

By now, you’re probably familiar with the basic structure of an argumentative essay. Most essays, including those at the higher academic level, generally follow a thesis statement , followed by supporting claims , evidence , and a conclusion . Most essays also address potential counterclaims and offer rebuttal arguments .

The structure is the easy part. Aside from side-stepping all logical fallacies, how do you write a persuasive essay that’s actually, well, persuasive?

Here are a few tips:

• Speak to your reader. Knowing your audience is crucial to making an effective argument. What ideas are they likely to resonate with? What vocabulary and word choice will they most likely understand? Even if you don’t know your exact audience, speaking to them will help you make a genuine connection with your readers.
• Be concrete. Tie your thesis and arguments to the real world, even if your writing isn’t about real world issues. For example, an essay about the values of optimism can demonstrate those values through concrete examples: anecdotes, case studies, and psychological research, as well as moral and philosophical reasoning.
• Sound like yourself. Using a lofty vocabulary or purple prose will not win over any of your readers. Part of building effective ethos is sounding like a reasonable voice, one which the reader can trust and rely on, and that comes through employing smart writing style strategies .
• Know your rhetorical devices . A good balance of ethos, pathos, logos, and kairos will go a long way towards persuasiveness. And, knowing different types of argumentative and rhetorical structures will certainly come in handy. Similes, metaphors, and analogies are also great ways of demonstrating an argument.

Of course, these strategies alone don’t make for great persuasive writing. Having solid logic behind your reasoning and carefully crafted arguments will make your essays shine. As such, let’s look at some common logical fallacies and discuss how you can avoid them.

Logical Fallacies Examples

A good persuasive essay requires good thinking, writing, researching, and revising. Nonetheless, even the best thinkers are prone to these common logical fallacies. Understanding the errors of logic in this list, how they happen, and how to avoid them will strengthen your ability to argue and to identify faulty arguments.

We’ve sectioned this list by the different types of logical fallacies. Let’s examine them below!

Fallacies of Relevance are any number of informal logical fallacies in which an irrelevant argument is presented as relevant, distorting the conclusion or misdirecting the audience. You may have heard of the red herring logical fallacy before; most fallacies of relevance are, in some way, red herrings.

Fallacies of Relevance are logical fallacies in which an irrelevant argument is presented as relevant, distorting the conclusion or misdirecting the audience.

Let’s look closer at each one.

Ad Hominem Logical Fallacy

An Ad Hominem (Latin: “against the person”) attack is a logical fallacy in which the person is argued against, rather than the argument the person is making. In other words, it attacks the source but not the credibility of the argument.

Here are a few examples:

• The car salesman is lying about the quality of the car because it’s his job to sell cars.
• “You have no reason to raise the minimum wage if you’ve never run a business before. ”
• “I just saw my boss do a hit and run. Clearly, this means he’s a bad boss. ”

None of these examples actually engage with logic. Accusing someone of lying or ignorance is a lazy way of avoiding the argument. And, while someone who commits a hit and run has questionable ethics, there isn’t a clear relationship between bad driving and bad leadership.

If any of these attacks sound familiar, it’s because Ad Hominem is a prominent feature of our cultural and political landscape. Now, there is something to be said about questioning the ethos of the person making an argument. There are plenty of people, politicians and otherwise, who do have ulterior motives and hidden agendas behind their logic and reasoning.

However, in good argumentation, you cannot simply question the ethos of the person. You must engage with the arguments themselves; an Ad Hominem attack is simply a distraction, meant to make the audience angry or distracted from the issues at hand.

In good argumentation, you must engage with the arguments themselves.

Appeal to Consequences Logical Fallacy

The Appeal to Consequences argues that a premise is correct or incorrect based on whether the outcome is positive or negative. In other words, if a certain hypothesis leads to an undesirable consequence, the hypothesis “must” be wrong; if the consequence is positive, it “must” be right.

For example:

• Rent prices are bound to decrease because more people will be able to afford housing.
• It’s impossible to spend all your money gambling because then you couldn’t afford to eat.

Of course, valid hypotheses can result in negative outcomes, because an argument is valid irrespective of its outcome. And invalid hypotheses can suggest positive outcomes because “wishful thinking” is inherently a logical fallacy.

Appeal to Emotion Logical Fallacy

An Appeal to Emotion occurs when an argument tries to evoke an emotional response, rather than a logical one. For example:

• “You should eat your food because a poor, starving child in Africa doesn’t have any. ”
• (Appealing to your sense of guilt.)
• “If you pass this law, thousands of your constituents will ransack your office. ” (Appealing to your sense of fear.)
• “You can’t raise the minimum wage; your childhood enemy might make more money. ” (Appealing to your sense of hatred.)

Now, this logical fallacy is similar to the rhetorical device “pathos.” The difference is that, in good rhetoric, pathos is not the central argument. Pathos is a feature of good argumentation, because a good rhetorician knows which emotions to evoke from the audience and how those emotions inspire action or belief. But, when that emotional response is the desired outcome of the argument, without credible logic to back it up, then the speaker is trying to twist your feelings without good reasoning.

• Pathos-inspired logic: Martin Luther King, Jr.’s “I Have a Dream” speech included many examples of racial inequality, including how “one hundred years [after slavery], the Negro lives on a lonely island of poverty in the midst of a vast ocean of material prosperity”. Calling attention to something ostensibly unfair inspired action; elsewhere in the speech, King uses ethos and logos to demand a better life for Black Americans—which, for the skeptical member of King’s audience, will also improve the lives of all Americans.
• Appeal to Emotion fallacy: Let’s say King’s entire speech was just pathos. Or, let’s say King started arguing “if we don’t achieve racial equality, America will burn and everyone will die.” Then, the purpose of the speech would have been simply to make people angry and afraid, rather than to push for a more equitable society. The difference, here, lies in the purpose of the speech, and in the facts and logic played out on the national stage.

Appeal to Force Logical Fallacy

An Appeal to Force argues that physical or emotional harm is a consequence of certain arguments. It is related to the Appeal to Emotion in that it inspires fear.

• “If you don’t work extra hours without pay, you’ll be fired without severance .”
• “Maybe you’ll agree with me after I break a few of your ribs .”
• “If you don’t vote for me, your rent will skyrocket, the streets will be riddled with crime, and your children will have no future to speak of.”

Obviously, these arguments aren’t arguments at all: they’re trying to coerce you into agreeing with something that has no logical backing.

Appeal to Ignorance Logical Fallacy

The Appeal to Ignorance is a logical fallacy in which something must be true because there is no evidence against it . In other words, the fallacy is that the absence of counterevidence means there is no counterevidence. However, the absence of something is not an argument for its own absence: “absence of evidence is not evidence of absence.”

• Aliens do not exist because we have not come into contact with them.
• We haven’t come into contact with the core of a black hole, so you cannot assume that the core of a black hole is not made up of bird’s feathers.

The Appeal to Ignorance is especially consequential in the courtroom. For example, if you don’t have an alibi, that means you must have killed the victim. The logic isn’t sound, but the wrong jury, or a jury with strong prejudices, might buy it.

Appeal to Improper Authority Logical Fallacy

The Appeal to Improper Authority argues that an argument must be true because it came from an authority figure. This is misplaced ethos, because the logical fallacy assumes one’s authority automatically grants ethos on a position, instead of that ethos being earned through argumentation.

• “She has bipolar disorder. Trust me, I’m a psychology major. ”
• “ My high school gym teacher told me never to use ice on a sprained ankle.”

Sometimes, the Appeal to Improper Authority is an appeal to the wrong kind of authority. Being a psychology major isn’t justification for diagnosing someone; you should have an advanced degree and research experience. You should also have conducted a psych evaluation on the person in question. Other times, this Appeal isn’t enough justification; you still need to back your arguments with logic. What knowledge does your degree as a psych major give you to make a certain conclusion?

However, this is not license to assume something is incorrect just because it comes from an authority figure. For example, many people assume that the advice from a doctor must be wrong. While doctors do make mistakes, attacking the credibility of a doctor, rather than the science behind the decisions they make, is just an Ad Hominem.

Appeal to Tradition Logical Fallacy

The Appeal to Tradition logical fallacy says “we’ve always done it this way.” Rather than interrogate the logic behind a certain action, the argument assumes the action is logically sound because it’s been done for a certain amount of time.

• “Our family has always voted this way. Grandpa would kill me if I voted any other way!” (This neglects that a party’s positions change over time, as well as the political needs of a city/state/nation.)
• “ Women have always tended to the hearth and raised the kids. It’s easier this way!”

Sometimes, tradition is rooted in logic. But a good argument will illuminate that logic, and that logic’s relevance to the modern day, rather than assume the logic exists.

Argument From Incredulity Logical Fallacy

An argument from incredulity occurs when you argue that something can’t be true solely because it’s difficult to imagine, hard to understand, or else doesn’t conform to your particular worldview.

• Not believing we landed men on the moon.
• “I don’t understand your argument, therefore it isn’t logical.”
• “Your argument doesn’t align with my spiritual or political beliefs. Therefore, it’s wrong.”

This logical fallacy is often at play among conspiracy theorists, but it’s just another easy way to avoid the hard work of understanding and responding to logically sound arguments.

Argumentum ad Populum Logical Fallacy

The Argumentum ad Populum (Argument to the People, or “to Popularity”) is based on the premise that, if a certain number of people believe in the argument, it must be correct. This logical fallacy has a few different manifestations, including:

• The Bandwagon Argument: “Most people believe that the iPhone is superior, so you should buy an iPhone.”
• The Patriotic Argument (Jingoism): “You must buy an iPhone, because you’re supporting an American company with American values. Any other phone is tantamount to treason!”
• The Snob Argument: “Anyone who’s rich and important has an iPhone. So, you should have one if you want to be rich and important.”

This argument can be difficult to respond to, because if the argument is wrong, you might be implying that the masses have poor logic. Well, sometimes they do. Argumentum ad Populum is simply peer pressure, not sound logic.

Genetic Fallacy

The Genetic Fallacy occurs when you base the validity, or invalidity, of an argument solely on its source. Ad Hominem can be a type of Genetic Fallacy, but you can also attack an argument’s validity by saying it came from Wikipedia, YouTube, or a certain publisher or newspaper.

• “My parents told me not to trust dentists, so I don’t trust dentists .” (This is also an Appeal to Improper Authority.)
• “Your information comes from Wikipedia. Clearly, your argument isn’t grounded on reliable data. ”

You should certainly interrogate the source of information. However, good critical arguments will examine the research and methodologies behind that data, instead of just assuming invalidity.

Irrelevant Conclusion Logical Fallacy

The logical fallacy Irrelevant Conclusion, also known as ignoratio elenchi, describes a conclusion that is irrelevant to the premises allegedly supporting it.

• “Fire can’t be dangerous to humans because it keeps us warm in the winter. ”
• “Cane sugar is good for you because it’s white, which is a pure color .”

Most logical fallacies of relevance are, in some way, fallacies of Irrelevant Conclusion.

Straw Man Argument Logical Fallacy

The Straw Man Argument occurs when you refute someone’s argument by responding to a completely different, utterly warped argument that the original person did not make. In other words, you distort an argument to make it easier to attack. The Straw Man is often a kind of Ad Hominem. It might look something like this:

Person 1: Investing money in your happiness today helps keep you motivated for longer term goals.

Person 2: What are you, some kind of hedonist?

This logical fallacy also occurs when you quote someone out of context. Think Fred Jones saying “I think Coolsville sucks !” in Scooby-Doo 2: Monsters Unleashed .

Tu Quoque Logical Fallacy

Tu Quoque is another form of Ad Hominem, in which a person’s behavior or past beliefs are called into question to discredit their current argument.

• “Doctors tell you not to smoke, but doctors smoke all the time .”
• “ You cheated on your girlfriend , so why can’t I?”

Tu Quoque is sometimes called the Appeal to Hypocrisy. The importance of hypocrisy is not to be understated, but when it comes to logic and reasoning, someone being a hypocrite doesn’t necessarily discredit the argument at hand.

Fallacies of Unacceptable Premises attempt to introduce premises that, though possibly true, do not ultimately support the argument’s conclusions. This is different from fallacies of relevance because the premises are relevant, they just don’t support the conclusions.

Fallacies of Unacceptable Premises attempt to introduce premises that, though possibly true, do not ultimately support the argument’s conclusions.

Begging the Question Logical Fallacy

Begging the Question is a logical fallacy in which the validity of the conclusion is buried in the premise of the argument. In other words, the logic undergirding an argument makes assumptions that, when questioned, reveal the argument’s lack of reasoning. It is a premise restating the conclusion without supporting the conclusion.

• This is just saying “I’m the boss” in two different ways. It doesn’t actually explain why the boss gets to make those decisions.
• Well, yes. That’s the definition of a bestseller. But this doesn’t explain why the apple turnover sells so well.
• The premise is saying the same thing as the conclusion, perhaps with a moral appeal attached. Take it a step further: what benefits do we get from raising the minimum wage? The argument hasn’t been made yet .

Begging the Question happens a lot more often than you might think. By knowing this logical fallacy and noticing it, you’ll be able to question a person’s logic (or lack thereof) much more directly.

Division Fallacy

The division fallacy occurs when you assume that something true for a whole entity is also true for each individual component of that entity. For example:

• There is a lot of money in the technology sector.
• You work in the technology sector.
• You make a lot of money.

Plenty of people make a lot of money in tech, but this assumption is riddled with errors. There are some low-paying positions in tech, and this argument does not take into account how money is distributed in tech.

False Dilemma Logical Fallacy

A False Dilemma occurs when an argument presents the audience a limited number of sides to an issue, when many more sides exist. By doing this, the argument hopes to make you choose its side over the other, when the situation is actually much more nuanced.

• “You either support the war or you hate your country.”
• “In high school, you’re either a nerd, a jock, or a prep.”
• “Anything that doesn’t support a free market Capitalist economy is clearly part of an authoritarian Communist agenda.”

Binary thinking is a prominent—and dangerous —way of thinking. Good, honest rhetoricians will recognize that one issue can have many sides, and that good thinking acknowledges gray spaces and ambiguities, rather than trying to paint a black and white picture of the world. Rhetoricians should be confident in their arguments, but if someone presents themselves as knowing everything , especially if they present a limited number of sides to an issue, be skeptical.

Slippery Slope Logical Fallacy

The Slippery Slope fallacy argues that a small first step will result in a later, usually catastrophic major event. It amplifies the stakes of an argument without providing clear justification that the catastrophe will occur.

• “Failing this one test means you might fail the class, which all but guarantees you won’t obtain your Master’s Degree. ”
• “Weed is a gateway drug. Within a few years, you’ll be a jobless, homeless addict craving your next fix. ”
• If you give this person a pass for being late, you’ll have to give everyone a pass, and then the rules won’t matter anymore. 
• Lowering the voting age to 16 will encourage 12 year olds to try and vote. Eventually, this country will be run by children. 

This isn’t to say that all catastrophizing is automatically a Slippery Slope. Rather, it’s to note that small decisions can lead to a variety of outcomes; if a catastrophic outcome is predicted, that prediction must be underscored with clear, structurally sound logic.

Hasty Generalization Logical Fallacy

A Hasty Generalization is a logical fallacy where a conclusion is drawn from a limited amount of information. The argument simply does not have enough data to support the conclusion it arrives at.

• “My neighbor has tanned every day for the past 20 years and has flawless skin. Therefore, sun exposure doesn’t cause skin cancer. ”
• “Someone on the South Side flipped me off today. Everyone who lives there is so mean. ”
• “1000 people committed food stamp fraud last year. All 3 million of them must be gaming the system. ”

As you can see, Hasty Generalizations are really useful tools for assigning blame and turning the audience against a certain group of people. If you want to claim something about a group or an outcome, a good argument uses robust, clearly organized data to support that claim.

Faulty Analogy Logical Fallacy

A Faulty Analogy is the use of an analogy to compare two things that do not merit a direct comparison. (In brief, an analogy is a literary device in which two or more discrete things are compared as equals.) Using a Faulty Analogy misrepresents the topic at hand.

• There’s a false equivalence of those different “worlds” here.
• Part of the reason for this difference is that more people drive than take opiates . In any case, this is also presenting a False Dilemma: why can’t we improve both situations?
• This assumes that the two chance happenings are related to one another. But luck does not operate in any logical or meaningful way. The two simply can’t be compared.

When someone makes an argument using an analogy, ask yourself whether the items being compared exist on the same playing field. If they don’t, a logical fallacy is likely at play.

The Fallacy Fallacy

The Fallacy Fallacy occurs when you assume that an argument is incorrect because it contains a logical fallacy.

Now, that might seem ironic , or even completely contradictory. Isn’t that the entire point of this article?

What this means is, an argument can have the correct conclusion even if it uses a logical fallacy. The argument itself is incorrect, but the conclusion can still be true, it just needs to be reached using a different logic or set of data.

• Obviously, sharks can swim, but not because they’re not horses.
• It could very well be raining in Seattle right now. But the reason it’s raining has nothing to do with the existence of Seattle, it has to do with the weather conditions Seattle finds itself in.

Don’t disregard the existence of this common logical fallacy. If a conclusion seems accurate, or even just intriguing, approach it with a sense of curiosity. Sure, the argument you’re given might be wrong, but under what conditions might it be right? And why is that?

Good logical thinking doesn’t just call out bad arguments, it also creates opportunities to discover more about the world.

Formal fallacies are logical fallacies involving an error in deductive reasoning. As a refresher, deductive reasoning is the use of existing information (premises) to create new information (conclusions).

Formal fallacies are logical fallacies involving an error in deductive reasoning.

• A bird has wings, feathers, and claws.
• A cardinal has wings, feathers, and claws.
• A cardinal is a bird.

Formal fallacies include the following:

• Affirming the consequent
• Denying the antecedent
• Affirming a disjunct
• Denying a conjunct
• Fallacy of the undistributed middle
• Fallacy of four terms

You may have heard of the term non sequitur before. All formal fallacies are non sequiturs, because their conclusions do not follow the claims associated with them.

Affirming the Consequent Logical Fallacy

Affirming the Consequent occurs when the premise and the conclusion are switched in a formal argument. Let’s say you argue the following:

• If it is raining, then it is cloudy.
• It is rainy, thus
• It is cloudy.

Affirming the Consequent means switching the order of the latter two bullets. So, the logical fallacy would be:

• It is cloudy, thus
• It is raining.

This isn’t true, because it can be cloudy without it raining. The “if” and “then” statements have been reversed, resulting in a conclusion that can’t be supported.

Denying the Antecedent Logical Fallacy

Denying the Antecedent occurs when you take a standard argument, put it in the negative, and then argue that the negative is just as true. In other words, you argue that the opposite of a true argument is just as true.

Let’s take the above example. This argument is correct:

The “antecedent” would look like this:

• It is not raining, thus
• It is not cloudy.

Obviously, it can be cloudy without it being rainy. The premise remains true, but assuming the inverse is also true leads to poor logic.

Affirming a Disjunct Logical Fallacy

Affirming a Disjunct arises out of the ambiguity of the word “or”. In formal logic, “or” can be inclusive (meaning “and/or”), or it can be exclusive (meaning “either/or”). Because of this ambiguity, an argument can seem as though it is creating a false binary, leading to a false conclusion.

• To get rich, you must work hard or network well.
• You got rich by networking well.
• Therefore, you did not work hard.

It is possible that the conclusion is true. It is equally possible that you worked hard and networked well. Affirming a Disjunct occurs when that “or” is interpreted as “exclusive,” rather than “inclusive.”

Denying a Conjunct Logical Fallacy

Denying a Conjunct follows a similar formal fallacy as Affirming a Disjunct, in which the argument seems to be creating a binary that actually cannot be supported. In this logical fallacy, you argue that two things cannot both be true, then conclude that if one is false, the other must be true.

• You cannot be both an American and a North Korean.
• You are not North Korean, thus
• You are American.

Obviously, you can be something other than American or North Korean. The premise of the argument is true, because you can’t have dual citizenship between the two countries, but the interpretation of that premise as a binary is false.

Fallacy of the Undistributed Middle

In the Fallacy of the Undistributed Middle, the middle term, which links the premise to the conclusion, doesn’t actually have a relationship to the premise or the conclusion, leading to a faulty conclusion.

• All birds have beaks.
• An octopus has a beak, thus
• An octopus is a bird.

The conclusion is obviously incorrect. Moreover, the middle term isn’t doing any work for the argument. It tells us that octopi and birds have beaks, but it doesn’t tell us the relationship between birds and octopi, nor does the argument say that birds are the only organisms with beaks. The argument is creating a connection that doesn’t exist in the argument, leading to a conclusion it cannot support.

Fallacy of Four Terms

The Fallacy of Four Terms occurs when a standard syllogistic argument (the kind we’ve been referencing throughout this section) has four or more terms, rather than the requisite three.

By terms, we don’t mean bullet points, we mean the points of comparison in an argument. Here’s a proper syllogism:

• All books (P) are written by humans (Q).
• If this text is a book (P), then
• It was written by a human (Q).

The letters in parentheses highlight that a syllogism follows this structure:

• All Ps are Qs

There are variations to a proper syllogistic argument, but they always have 3 terms: a PQ term, a P term, and a Q term.

Here’s the Fallacy of Four Terms:

• Manhattan’s streets (A) have a grid pattern (B).
• A waffle (X) is made with a gridded iron (Y).
• Manhattan is a waffle.

This fallacy rests on the assumption that a grid and a gridded iron are the same term, but they’re distinct. You thus arrive at an incorrect conclusion because you’ve made a random comparison between completely unalike ideas.

Here’s another example, to further illustrate the point, as well as to show how subtle this fallacy can be:

• Nothing (A) beats a cold glass of water on a hot day (B).
• A warm glass of water (X) is better than nothing (Y).
• A warm glass of water is better than a cold glass of water.

“Nothing” is being used in multiple colloquial senses, which creates a really confusing argument here. It seems like there are only 3 terms, but “nothing” is employed in two different senses (there is nothing superior vs. something is better than nothing). As a result, you get a conclusion that, well, some people might agree with, but ultimately isn’t grounded in any meaningful logic.

The common logical fallacies above all rely in some way on faulty syllogistic reasoning, whether the fallacy is in the logic or in the premises themselves. The following fallacies are different errors in logic and reasoning, which can contribute to faulty arguments, but are not necessarily syllogistic.

Correlation Vs Causation

Correlation Vs Causation occurs when you assume that a correlation implies an actual relationship between two things. For example, you might notice that people who get spray tans often wear flip flops. If you assume that getting a spray tan encourages you to wear flip flops, you’re committing this logical fallacy—there are plenty of reasons why this correlation might occur, but spray tans do not cause flip flop wearing.

Hypothesis Contrary to Fact

A Hypothesis Contrary to Fact is, simply, speculation without concrete evidence. It is an argument that, under different circumstances or historical events, the present or the future would certainly look a certain way. For example, “if you had gotten a job in finance, you’d be making loads of money right now.” This claim doesn’t take into account any number of factors: the state of the finance industry, your ability to perform finance-related work, etc.

“I’m Entitled to My Opinion”

This logical fallacy conflates opinion with fact. It is ultimately a kind of red herring. Let’s say I argue “it always rains when it’s sunny.” This is wrong; you call me out on this. I might reply saying “you can tell me I’m wrong, but I’m entitled to my opinion.” As a result, I’ve evaded the work of defending my argument or responding to yours, but the issue in question is not a matter of opinion.

Loaded Question

A Loaded Question inserts an unfounded claim into a question in an attempt to make the audience assume something untrue. I might ask you “Are you really going to eat strawberry ice cream when artificial strawberry flavoring gives you cancer?” I’ve stated a claim as though it were true, offering no justification and ultimately coercing you into believing something false.

Middle Ground

The Middle Ground fallacy assumes that the truth lies somewhere between two opposing sides. Let’s say two people are arguing about the color of Kirkjubøargarður , a farm in the Faroe Islands. One person argues it’s black; the other says it’s white. The person who says it’s white then argues “well, it must be somewhere in the middle. Let’s say it’s steel gray.” Yet the house is undeniably black.

This logical fallacy makes use of the existence of the False Dilemma; some things simply are black and white. Many politicians will use this argument to gain some concessions in their favor even when their position is ultimately and entirely wrong.

No True Scotsman

The No True Scotsman argument is an appeal to “purity,” in which a person argues that a true example of something doesn’t perform a certain behavior. See it played out in this conversation:

• Person 1: All New Yorkers work multiple jobs.
• Person 2: My uncle lives in New York, and only works one job.
• Person 1: Only real New Yorkers work multiple jobs.

This logical fallacy creates an arbitrary purity test, and often makes unfair arguments about a certain identity. You can imagine how this argument can be wielded much more perniciously: “only true Americans eat meat. Since you’re a vegan, you must be a Communist.”

Single Cause

The Single Cause fallacy assumes something occurs because of only one cause. A topical example of this is inflation in the year 2023. Some people argue inflation is because of supply chain issues; others argue it’s because of poor trade policy; others argue it’s because of corporate greed; others argue it’s because of rising wages and low unemployment. In truth, all of these are causes of inflation, as well as other causes not mentioned here.

Slothful Induction

Slothful Induction can also be called an Appeal to Coincidence. Instead of acknowledging the likely relationship between two things, you argue that something keeps happening because of coincidence. “Sure, I keep drinking while driving, but all of my DUIs are because people keep slowing their cars in front of me.” It is an abnegation of accountability.

Texas Sharpshooter

The Texas Sharpshooter fallacy occurs when you draw a conclusion from a limited amount of data. It is a process of shooting a gun at a wall and then painting a bullseye around the bullet hole. As a result, you exclude the information that actually negates or challenges your argument.

For example, you might argue “I got into Harvard because I studied hard, did athletics and extracurriculars, and wrote a good essay.” What you failed to mention is the $5,000,000 donation your dad gave to the school.

Or, “Brian and Sally were made for each other: they both like ice cream, Russian novels, knitting, long walks on the beach, and they both dislike hypocrisy.” Perhaps you didn’t know this: Brian is also gay.

Write Without Logical Fallacies at Writers.com

Good arguments rarely happen in a vacuum: they develop out of a process of feedback, debate, and collaboration. If you’re writing for periodicals, news outlets, or any other form of CNF, our upcoming creative nonfiction classes might be for you.

Sean Glatch

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Friday, March 18, 2016

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Logical Fallacies

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Fallacies are common errors in reasoning that will undermine the logic of your argument. Fallacies can be either illegitimate arguments or irrelevant points, and are often identified because they lack evidence that supports their claim. Avoid these common fallacies in your own arguments and watch for them in the arguments of others.

Slippery Slope: This is a conclusion based on the premise that if A happens, then eventually through a series of small steps, through B, C,..., X, Y, Z will happen, too, basically equating A and Z. So, if we don't want Z to occur, A must not be allowed to occur either. Example:

If we ban Hummers because they are bad for the environment eventually the government will ban all cars, so we should not ban Hummers.

In this example, the author is equating banning Hummers with banning all cars, which is not the same thing.

Hasty Generalization: This is a conclusion based on insufficient or biased evidence. In other words, you are rushing to a conclusion before you have all the relevant facts. Example:

Even though it's only the first day, I can tell this is going to be a boring course.

In this example, the author is basing his evaluation of the entire course on only the first day, which is notoriously boring and full of housekeeping tasks for most courses. To make a fair and reasonable evaluation the author must attend not one but several classes, and possibly even examine the textbook, talk to the professor, or talk to others who have previously finished the course in order to have sufficient evidence to base a conclusion on.

Post hoc ergo propter hoc: This is a conclusion that assumes that if 'A' occurred after 'B' then 'B' must have caused 'A.' Example:

I drank bottled water and now I am sick, so the water must have made me sick.

In this example, the author assumes that if one event chronologically follows another the first event must have caused the second. But the illness could have been caused by the burrito the night before, a flu bug that had been working on the body for days, or a chemical spill across campus. There is no reason, without more evidence, to assume the water caused the person to be sick.

Genetic Fallacy: This conclusion is based on an argument that the origins of a person, idea, institute, or theory determine its character, nature, or worth. Example:

The Volkswagen Beetle is an evil car because it was originally designed by Hitler's army.

In this example the author is equating the character of a car with the character of the people who built the car. However, the two are not inherently related.

Begging the Claim: The conclusion that the writer should prove is validated within the claim. Example:

Filthy and polluting coal should be banned.

Arguing that coal pollutes the earth and thus should be banned would be logical. But the very conclusion that should be proved, that coal causes enough pollution to warrant banning its use, is already assumed in the claim by referring to it as "filthy and polluting."

Circular Argument: This restates the argument rather than actually proving it. Example:

George Bush is a good communicator because he speaks effectively.

In this example, the conclusion that Bush is a "good communicator" and the evidence used to prove it "he speaks effectively" are basically the same idea. Specific evidence such as using everyday language, breaking down complex problems, or illustrating his points with humorous stories would be needed to prove either half of the sentence.

Either/or: This is a conclusion that oversimplifies the argument by reducing it to only two sides or choices. Example:

We can either stop using cars or destroy the earth.

In this example, the two choices are presented as the only options, yet the author ignores a range of choices in between such as developing cleaner technology, car-sharing systems for necessities and emergencies, or better community planning to discourage daily driving.

Ad hominem: This is an attack on the character of a person rather than his or her opinions or arguments. Example:

Green Peace's strategies aren't effective because they are all dirty, lazy hippies.

In this example, the author doesn't even name particular strategies Green Peace has suggested, much less evaluate those strategies on their merits. Instead, the author attacks the characters of the individuals in the group.

Ad populum/Bandwagon Appeal: This is an appeal that presents what most people, or a group of people think, in order to persuade one to think the same way. Getting on the bandwagon is one such instance of an ad populum appeal.

If you were a true American you would support the rights of people to choose whatever vehicle they want.

In this example, the author equates being a "true American," a concept that people want to be associated with, particularly in a time of war, with allowing people to buy any vehicle they want even though there is no inherent connection between the two.

Red Herring: This is a diversionary tactic that avoids the key issues, often by avoiding opposing arguments rather than addressing them. Example:

The level of mercury in seafood may be unsafe, but what will fishers do to support their families?

In this example, the author switches the discussion away from the safety of the food and talks instead about an economic issue, the livelihood of those catching fish. While one issue may affect the other it does not mean we should ignore possible safety issues because of possible economic consequences to a few individuals.

Straw Man: This move oversimplifies an opponent's viewpoint and then attacks that hollow argument.

People who don't support the proposed state minimum wage increase hate the poor.

In this example, the author attributes the worst possible motive to an opponent's position. In reality, however, the opposition probably has more complex and sympathetic arguments to support their point. By not addressing those arguments, the author is not treating the opposition with respect or refuting their position.

Moral Equivalence: This fallacy compares minor misdeeds with major atrocities, suggesting that both are equally immoral.

That parking attendant who gave me a ticket is as bad as Hitler.

In this example, the author is comparing the relatively harmless actions of a person doing their job with the horrific actions of Hitler. This comparison is unfair and inaccurate.

hypothesis contrary to fact

The fallacy of a hypothesis contrary to fact occurs when an arguer uses a fictional scenario to press a point about current states of affairs. While such a hypothesis can be valuable rhetorically or as a thought experiment, when an unverifiable hypothesis is used argumentatively, it is a fallacy.

"If patriarchy had never existed and we'd always had matriarchy, then we would still be living in grass huts. Therefore, patriarchy is good."

"If we'd never taken the dollar off the gold standard, our economy would be ten times bigger than it is today. Therefore, we should return to the gold standard."

Primary links

Avoiding logical fallacies.

Logic can go wrong in many ways. We’ve talked about building logical arguments. Now let’s consider how to avoid building illogical ones. The logical fallacies below can slip into your own and others’ arguments. Learn to identify them.

Distortions in Logic

(Instead of engaging the claim, the response dismisses its importance.)

(Does this mean we need to minimize or maximize the amount of water?)

(This claim dismisses opposition by saying poverty is just a fact of life.)

(This claim generalizes from some spousal abuse to all domestic violence.)

(In place of an argument, the same assertion is made three times.)

(To answer the question would be to admit to destroying the country.)

(This statement incorrectly assumes that the president’s location caused the 9/11 attacks.)

(This analogy does not accurately represent the process, in which the winner becomes arguably the most powerful person in the world.)

(This claim swaps the cause and the effect. The worsening economy causes the Fed to lower interest rates, not the other way around.)

(This claim ignores the difference between free speech and treason.)

(The agency can function on a reduced budget without shutting down.)

(This statement ignores the long evolution of both parties.)

(Both candidates won’t back down, so both should get the same praise or blame.)

(This statement does not follow. A person’s body fat percentage does not relate to his or her ability to balance governmental budgets.)

Your Turn Find a political debate online and listen to it. Write down as many examples as you can of the fallacies on these two pages.

(Instead of changing the false assumption that all Scotsmen are brave, the person discounts the counterexample of cowardly Andrew.)

(This statement means “We should get rid of harmful influences,” an idea so obvious that it really doesn’t need to be stated.)

(This oversimplification ignores the fact that such an act would catastrophically devalue the dollar.)

(This statement applies a reasonable principle to absurd specificity.)

(The language in this statement allows for no reasonable discussion.)

(Immigration reform does not require pardoning all illegal activity.)

(That a politician wants to destroy the country is a dummy argument.)

Your Turn Pick four of the fallacies on this page and write your own examples. Share your answers with a partner and discuss the faulty logic in each.

Misusing Evidence

(Someone else’s bad behavior doesn’t justify one’s own bad behavior.)

(Absence of evidence is not evidence of absence.)

(A proposal should be accepted on its own merits, not due to hard work.)

(A sentimental name doesn’t make peanut butter worth buying.)

(An actor who plays a doctor is not a medical authority.)

(The horror of the idea does not preclude its possibility.)

(Actually, quantum physicists have proven this idea.)

(This ad hominem attack diverts attention from the real issue: taxes.)

(A stronger argument would focus on the value of the paper.)

(The thousands who are injured are a tiny fraction of the millions who use power tools safely and who rely on them to make a living.)

(There is no way to prove or disprove what would have happened if the other candidate had won, so the argument is meaningless.)

(The use of numbers baffles the audience into acceptance.)

(World hunger is a serious problem that shouldn’t be dismissed with a joke.)

(The Ebola virus, a separate problem, should not be used to distract from the abhorrent use of child soldiers.)

(Threats are never an acceptable form of persuasion.)

Your Turn Watch commercials on television or on the Internet and write down two examples of the misuse of evidence on pages 111–112 .

Additional Resources

Web Site: Fallacies

Web Page: Logical Fallacies

Web Page: Common Fallacies in Reasoning

Web Page: Fallacies of Ambiguity

Web Page: Marketing Plots

Web Page: Hasty Generalization

Video:  Correlation and Causation

Web Page: False Cause

Web Page: False Dichotomy

Web Page: Non Sequitur

Blog Post: The New Illiteracy--Obfuscation

Web Page: Reductio ad Absurdum

Web Page: Slippery Slope

Web Page: Argumentum Ad Hominem

Web Page: Bandwagon Appeal

Web Page: Red Herring

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