As discussed in Chapter Two, an argument's quality depends on the relationship between its premises and conclusion. A good argument meets established criteria; failure to meet these criteria results in a flawed or bad argument, known as a fallacious one. A fallacy is a defect in an argument consisting of something other than merely false premises.
Fallacies can arise in numerous ways but typically involve mistakes in reasoning or the creation of an illusion that makes a bad argument appear sound. These defects can relate to the argument's structure (form) or the content of its statements (premises or conclusion). Consequently, both deductive and inductive arguments can contain fallacies.
Based on the nature of the defect, fallacies are broadly categorized as formal or informal. An argument commits a formal fallacy if it contains a structural defect, violating a standard form of valid reasoning. Because the flaw is structural, formal fallacies can often be identified by inspecting the argument's form alone, irrespective of its content. These fallacies typically occur only in deductive arguments with identifiable structures. Conversely, an informal fallacy involves a defect that goes beyond structure, relating to the argument's content, context, or the way language is used. Informal fallacies often create illusions of relevance or sufficiency and cannot be detected merely by examining the argument's form; analysis of the content is required to uncover the error. This chapter focuses primarily on identifying and understanding various informal fallacies.
Upon successful completion of this chapter, you will be able to:
A fallacy is generally defined as a deficiency or logical error in an argument, stemming from reasons other than simply having false premises. Fallacies manifest in various forms, depending on the specific defect in the reasoning process or argument structure. This section discusses the general concept of fallacy and distinguishes between formal and informal types.
After completing this section, you will be able to:
Are you familiar with the term ‘fallacy’? Have you used it before? If so, what does ‘fallacy’ mean to you?
In logic, the term fallacy refers to a defect, flaw, or error in an argument's structure, reasoning process, or content (premises/conclusion) that weakens or invalidates the argument for reasons other than merely having false premises. Essentially, a fallacy represents a violation of the standard rules or criteria for good argumentation.
Before delving into specific fallacies, let's briefly recall the criteria for a good argument.
What are the standard criteria or principles of a good argument discussed previously?
Recall the principles discussed (often summarized by criteria like relevance, acceptability, sufficiency, and rebuttal). A good argument must have premises that are relevant to the conclusion, acceptable to a rational audience, sufficient (collectively) to justify the conclusion, and provide an effective rebuttal to anticipated challenges.
A premise is relevant if it makes a difference to the conclusion's truth or falsity. It is acceptable if a rational person ought to accept it based on evidence or common ground. Premises must also be sufficient in number, kind, and weight to adequately support the conclusion. Finally, a good argument anticipates and effectively refutes reasonable objections (rebuttal).
Therefore, a fallacy can be understood as the violation of one or more of these criteria. An argument remains good only as long as it meets these standards; if it violates any, it becomes flawed, or fallacious.
Fallacies are broadly classified into two groups: formal and informal. A formal fallacy arises from a defect in the argument's logical structure or form. Because the error is structural, formal fallacies can typically be identified by analyzing the argument's form without considering its specific content. They primarily occur in deductive arguments with recognizable structures (e.g., syllogisms). An informal fallacy involves a defect related to the argument's content, context, or language use, rather than just its structure. These fallacies often create illusions of support and cannot be detected solely by examining the form; analyzing the content and reasoning process is necessary to identify the flaw.
Formal fallacies pertain to deductive arguments with flawed structures. Consider this categorical syllogism:
All tigers are animals. (True)
All mammals are animals. (True)
Therefore, all tigers are mammals. (True)
This argument *seems* plausible because the conclusion is true, but its logical form is invalid:
All A are B.
All C are B.
-------------------
Therefore, All A are C.
Inspecting this form reveals its invalidity (known as the fallacy of the undistributed middle term). The specific content (tigers, animals, mammals) is irrelevant to identifying the structural flaw. Modifying the structure (e.g., interchanging C and B in the second premise) could create a valid form, though the original argument remains formally fallacious.
Another example of a formal fallacy, occurring in hypothetical reasoning:
If apes are intelligent, then apes can solve puzzles.
Apes can solve puzzles.
----------------
Therefore, apes are intelligent.
The form is:
If A, then B.
B.
----------------
Therefore, A.
This invalid form is known as Affirming the Consequent. The conclusion does not necessarily follow from the premises, even if the premises are true. The structural flaw makes it a formal fallacy.
Key points for distinguishing:
When evaluating arguments, look for standard deductive forms. If an argument fits such a form but is invalid due to improper term or statement arrangement, it commits a formal fallacy. If the flaw lies elsewhere, it's likely an informal fallacy.
Informal fallacies represent errors in reasoning that cannot be detected merely by examining the argument's logical structure. The flaw lies in the content, the context, or the way language is used. Consider this argument:
All factories are plants.
All plants are things that contain chlorophyll.
Therefore, all factories are things that contain chlorophyll.
Structurally, this resembles a valid form:
All A are B.
All B are C.
----------------
Therefore, All A are C. (Valid form: Barbara syllogism)
Although the *apparent* structure (All A are B, All B are C, so All A are C) is valid, the argument about factories is clearly invalid because it has true premises leading to a false conclusion. The error lies in the *content*—specifically, the ambiguous use of the word "plants."
In the first premise, "plants" means industrial facilities. In the second, "plants" means biological organisms. Due to this shift in meaning (an informal fallacy called Equivocation), the actual logical form is closer to:
All A are B (factories are industrial facilities).
All C (biological organisms) are D (contain chlorophyll).
------------------
Therefore, All A are D. (Invalid)
This demonstrates how informal fallacies require analyzing content and meaning, not just superficial structure.
Logicians have classified numerous informal fallacies, often grouped for study. Following a common approach, we divide them into five categories: fallacies of relevance, weak induction, presumption, ambiguity, and grammatical analogy.
Fallacies of relevance occur when the premises of an argument are logically irrelevant to the conclusion, yet may seem psychologically relevant. The connection is emotional or circumstantial, rather than logical. This section covers eight common fallacies of relevance: Appeal to Force, Appeal to Pity, Appeal to the People, Argument Against the Person, Accident, Straw Man, Missing the Point, and Red Herring. (Note: Missing the Point is slightly different, involving an irrelevant conclusion rather than irrelevant premises).
After completing this section, you will be able to:
The shared characteristic of these fallacies is that the premises lack a genuine logical connection to the conclusion. They fail to provide real evidence. Instead, they often rely on emotional appeals or distractions to persuade the audience. Such arguments are sometimes termed non sequiturs ("it does not follow") or involve argumentative leaps, as there's no logical bridge from premises to conclusion. Identifying these fallacies requires distinguishing legitimate evidence from emotional manipulation or irrelevant information.
How would you define the Appeal to Force fallacy?
The Appeal to Force fallacy (Latin: *argumentum ad baculum*, "argument to the stick") occurs when an arguer attempts to persuade by threatening harm (physical or psychological) to the listener if they do not accept the conclusion. The threat is logically irrelevant to the conclusion's truth but psychologically coercive.
Consider this blatant example involving a physical threat:
Mr. Kebede, you have accused me of fraud and embezzlement. You must drop those charges. Remember, I know where you and your family live. If you don't drop the case, unfortunate things might happen. Understand?
This is fallacious. The threat ("unfortunate things might happen") provides no logical reason to believe the charges should be dropped, only a coercive incentive. The underlying structure is flawed:
Premise 1: If you do not drop the charges, harm will come to you/your family.
Premise 2 (Implicit): You want to avoid harm.
Conclusion: Therefore, you should drop the charges.
The threat's existence is irrelevant to the legitimacy of the charges.
The threat need not be physical. Consider psychological or economic coercion:
There's been much negative talk about our new company policy. Let me be clear: anyone wanting to keep their job here needs to understand that this policy is perfectly fair and reasonable. I will not tolerate employees who think otherwise.
This argument attempts to force acceptance of the policy's fairness (the conclusion) by threatening job loss (the force). The threat is logically irrelevant to whether the policy is *actually* fair. The implicit form is:
Premise 1: If you do not accept that the policy is fair, you will be fired.
Premise 2 (Implicit): You want to keep your job.
Conclusion: Therefore, you should accept that the policy is fair.
This uses psychological/economic force, not logical reasoning, to compel agreement.
The Appeal to Force fallacy works by psychologically pressuring the listener, often obscuring a missing logical connection. The listener feels compelled to agree due to the threat, not due to sound reasoning.
However, be cautious: simply mentioning a potential negative consequence does not automatically constitute this fallacy. For instance, warning someone "If you touch that live wire, you will be electrocuted" is not a fallacy but a legitimate warning based on causal reasoning. The fallacy occurs specifically when a threat is used to compel acceptance of a conclusion that is logically unrelated to the threat itself.
How would you define the Appeal to Pity fallacy?
The Appeal to Pity fallacy (Latin: *argumentum ad misericordiam*) occurs when an arguer attempts to support a conclusion by evoking pity or sympathy from the reader or listener, even though the pity evoked is logically irrelevant to the conclusion. While compassion is a valid human emotion, it doesn't substitute for logical evidence.
The structure often looks like this:
Premise 1: Person/group P is in a pitiful situation.
Premise 2 (Implicit): Pity should motivate action X.
Conclusion: Therefore, action X should be taken.
(Where action X is not logically justified by the pitiful situation alone).
The fallacy lies in using emotion to distract from the lack of relevant logical support.
Example:
The Headship position in the Department of Accounting should be given to Mr. Oumer Abdulla. Oumer has six hungry children to feed, and his wife desperately needs an operation to save her eyesight.
The conclusion is that Mr. Oumer should get the Headship position. The reasons provided relate to his difficult personal circumstances (hungry children, sick wife). While these circumstances evoke pity, they are logically irrelevant to whether Mr. Oumer is qualified or the best candidate for the Headship position (which should depend on factors like experience, qualifications, administrative skills). The argument illegitimately substitutes pity for relevant criteria.
Not all arguments involving pity are fallacious. Compassion can be a legitimate and relevant factor in certain contexts, particularly when deciding how to treat someone facing hardship through no fault of their own.
Example (Legitimate Appeal):
These twenty children survived a devastating earthquake that killed their parents and destroyed their homes. They are now orphans, living on the streets without support. Unless we contribute funds, their lives are in immediate danger. Therefore, we should help these children as much as possible.
Here, the conclusion (we should help) is arguably justified by the premises describing their dire situation. The children's plight evokes pity, but critically, their situation is due to factors beyond their control, making compassion and aid a relevant and reasonable response.
The key distinction often lies in whether the pity evoked is relevant to the conclusion being drawn. If the conclusion is about providing aid or showing leniency to someone suffering due to circumstances beyond their control, appealing to compassion can be legitimate.
However, if the conclusion concerns matters where objective criteria (like qualifications for a job, guilt in a crime, or the truth of a factual claim) are paramount, appealing solely to pity is usually fallacious. The fallacy occurs when pity is used to obscure or replace relevant evidence or criteria. If someone's hardship is largely their own fault, appealing to pity to excuse their actions or grant unearned benefits might also be considered fallacious.
How would you define the Appeal to the People fallacy?
The Appeal to the People fallacy (Latin: *argumentum ad populum*) attempts to persuade by appealing to people's desires to be loved, esteemed, admired, valued, recognized, or accepted by others. It leverages the powerful human needs for belonging and social approval to gain acceptance for a conclusion, often bypassing logical reasoning.
Example (Direct Approach - Mob Mentality):
I look out at you all, and I tell you, I am proud to be here. Proud to belong to a party that stands for what is good for our country. Proud to cast my lot with the kind of people who make this nation great... Yes, when I look at you hard-working patriots, I know *we* are right and *our* critics are wrong!
Here, the speaker uses emotionally charged language ("proud," "good for the country," "make this nation great," "hard-working patriots") to create a sense of group identity and shared values. The conclusion ("we are right and our critics are wrong") is supported not by logical evidence about the specific issue, but by appealing to the audience's desire to belong to this esteemed group. Accepting the conclusion becomes a way to affirm one's membership and patriotism. The strong feelings evoked are logically irrelevant to the truth of the conclusion.
The fallacy can also target individuals by appealing to their relationship with a group or social standards.
Example (Indirect Approach - Patriotism):
Mrs. Riley, are you saying that President Bush made a moral error when he decided to go to war with Iraq? I can’t believe my ears. That’s not how true Americans feel. You *are* an American, aren’t you, Mrs. Riley?
This pressures Mrs. Riley to conform to what the speaker presents as the "true American" viewpoint. Her nationality provides no logical basis for concluding the war was moral, but the appeal leverages her potential desire to be seen as patriotic and avoid social disapproval.
The direct approach, as seen, aims to create a mob mentality in a large group. The indirect approach targets individuals by focusing on their relationship to group norms or desires. Common forms of the indirect approach include:
These are frequently used in advertising and propaganda.
The Bandwagon Argument leverages the desire to fit in or conform to majority opinion or behavior. It suggests that because many people believe or do something, it must be right or desirable.
Example:
The majority of people in Ethiopia accept the practice of child circumcision as right. Therefore, you should also accept that child circumcision is right.
This argument commits the bandwagon fallacy if acceptance is urged *solely* because the majority approves. The popularity of a belief or practice does not logically guarantee its correctness or morality. It appeals to the listener's desire not to deviate from the group norm.
Is there a connection between sociocentrism and the bandwagon fallacy?
The Appeal to Vanity associates a product, idea, or course of action with admired, glamorous, or successful individuals. It implies that adopting the product or idea will make the listener similarly admired.
Example (Advertisement):
See famous footballer Frank Lampard wearing the latest Adidas shoes! Wear the shoes of champions! ADIDAS!
The implied message is: "If you wear these shoes, you too will be admired like Frank Lampard." The celebrity association provides no logical reason to believe the shoes are objectively good or suitable for the listener, but it appeals to the desire for admiration.
A snob typically admires those perceived as being in higher social classes and disdains those in lower classes, often valuing exclusivity. The Appeal to Snobbery leverages this desire to be part of an elite, superior, or exclusive group.
Example:
This new luxury watch is not for everyone. It's for the discerning few who appreciate true craftsmanship. You are clearly a person of distinguished taste, unlike the average consumer. Therefore, this watch is for you.
This argument appeals to the listener's desire to be seen as different from, and superior to, the "average" person. It suggests buying the product is a mark of exclusivity and refined taste, rather than providing logical reasons based on the product's intrinsic qualities.
Are all arguments referencing popular belief fallacious? Not necessarily. Sometimes, popular opinion or tradition can provide *some* relevant, albeit not conclusive, evidence.
Example (Based on Relevant Experience):
It is generally accepted by those who live in polar regions that penguins typically give birth when the winter is harshest. Thus, it's probable that penguins give birth during the harshest part of winter.
This is arguably not fallacious. The implicit assumption is that people living in the region are familiar with local wildlife patterns. Their consensus provides plausible evidence, though not definitive proof.
In other cases, widespread acceptance of a policy or principle might suggest it has undergone some form of collective deliberation or proven useful over time.
Example (Based on Established Norms):
The prohibition against killing other human beings is a fundamental principle accepted by virtually all societies and codified in moral and legal systems worldwide. Therefore, this principle should be taken seriously as a foundational ethical guideline.
Here, the near-universal acceptance doesn't *prove* the principle is absolutely correct, but it creates a strong presumption in its favor, suggesting it warrants serious consideration due to perceived historical utility or moral weight. The appeal is not just "everyone believes it," but implies a basis in collective experience or reason.
The key is whether the appeal to popularity serves as the *sole* or *primary* basis for the conclusion, or if it points towards underlying relevant factors (like expertise or historical justification).
What does the Argument Against the Person fallacy involve?
The Argument Against the Person fallacy (Latin: *argumentum ad hominem*, "argument to the man") typically involves two arguers. The first presents an argument. The second responds not by addressing the substance of the first person's argument, but by attacking the person presenting the argument.
Productive dialogue requires a degree of collaboration and trust, adherence to rules of politeness, and focusing on the issues. Ad hominem attacks violate this collaborative spirit by shifting focus from the argument to the arguer.
Attacking an arguer's character, circumstances, or consistency can be a powerful rhetorical move. It attempts to undermine the arguer's credibility, suggesting their arguments should be dismissed regardless of merit. If successful, it can effectively silence the person attacked, preventing meaningful participation in the dialogue.
Because of their potential to derail rational discussion and focus on irrelevant personal characteristics, ad hominem attacks are often treated as fallacious. However, as we'll see, not all arguments directed at a person are fallacious. The key is relevance.
The Argument Against the Person fallacy typically appears in three forms:
The respondent verbally abuses the arguer, attacking their character instead of their argument.
General Form:
Premise: Person A has a bad character (is dishonest, immoral, stupid, etc.).
Conclusion: Therefore, Person A's argument should be rejected.
The attack aims to destroy the arguer's credibility, implying their arguments are worthless due to personal flaws.
Example:
In defending animal rights, Mr. Abebe argues that the government should legislate minimum legal requirements for animal farming to prevent abuse. But we shouldn't accept his argument because he's a divorced drunk who can't even manage his own life.
This is fallacious. The argument attacks Mr. Abebe personally ("divorced drunk") instead of addressing the merits of his proposal about animal welfare legislation. His personal failings are logically irrelevant to whether legal protections for farm animals are justified.
Instead of direct abuse, the Ad Hominem Circumstantial fallacy attempts to discredit an opponent's argument by citing their circumstances (e.g., job, political affiliation, interests) as the reason for their position. It suggests the opponent is biased or predisposed to argue a certain way due to their situation, implying their argument lacks objectivity.
Example:
Haile Selassie I argued in the League of Nations that member states should assist Ethiopia against Fascist Italy. But we shouldn't listen to him. Of course he argues this way; he only wants to regain his power once the Italians are expelled.
This attacks the King's alleged motive (regaining power) based on his circumstances, rather than evaluating the reasons for League intervention (e.g., international law, aggression). The arguer dismisses the argument by pointing to the arguer's situation.
The Tu Quoque fallacy (Latin for "you too") attempts to discredit an argument by pointing out that the person presenting it fails to act consistently with their own conclusion or advice. It essentially accuses the arguer of hypocrisy.
General Form: "How can you argue that I should stop doing X when you do (or have done) X yourself?"
Example:
Patient to Doctor: Look, Doctor, you can't tell me to quit smoking. You smoke yourself! How can you advise me to quit when you haven't?
This is fallacious because the doctor's personal habits are logically irrelevant to the validity of the medical advice (based on evidence about smoking's health effects). While the doctor's behavior might seem inconsistent or hypocritical, it doesn't undermine the *reasons* why the patient should quit smoking. The advice might be sound even if the advisor doesn't follow it.
What relationship exists between the Tu Quoque fallacy and the standard of practical consistency?
While practical consistency is desirable, a lack thereof in the arguer doesn't automatically invalidate their argument's logic or conclusion.
Are all arguments directed at a person fallacious? No. Information about an arguer can be relevant in specific contexts, particularly when evaluating their credibility as a source of information (e.g., testimony).
In legal settings, questioning a witness's character for veracity (honesty) through evidence of past lying or bias can be legitimate (a form related to ad hominem abusive, but relevant to credibility). The aim is to assess the reliability of their testimony, not dismiss a separate logical argument they might make.
Similarly, pointing out circumstances that might genuinely bias an arguer's judgment can be relevant, *if* the argument relies heavily on their potentially biased perspective rather than on objective evidence.
Pointing out an arguer's circumstances (ad hominem circumstantial) can be relevant if their argument relies implicitly on their impartiality or special insight, which might be compromised by those circumstances. For example, people's social, economic, or political positions can influence their perspectives. Acknowledging this potential bias can be part of a critical evaluation.
However, it becomes fallacious when used to dismiss an argument *solely* because of the arguer's circumstances, without addressing the argument's substance. The mere fact that someone benefits from a position doesn't automatically mean their arguments for it are invalid, though it might warrant closer scrutiny for bias. Consider an argument from a medical association director:
Mr. Abdella, director of the national medical association, argued that given the heavy responsibilities and long hours worked by doctors, the government should significantly increase their salaries and benefits.
Is this argument immediately fallacious (ad hominem circumstantial) because Mr. Abdella, as director, benefits from such increases? Not necessarily. While his circumstance suggests potential bias, the argument should be evaluated on its merits: Are doctors actually overworked and underpaid relative to their responsibilities and the country's economic context? If the premises about workload are true and the salary comparison is relevant and accurate, the argument might be reasonable, despite the arguer's position. Dismissing it *only* because of his role would be fallacious. Evaluating the argument requires assessing the evidence presented, not just the arguer's circumstances.
Premises should provide sufficient grounds for accepting the conclusion. Fallacies of Weak Induction occur when the premises, although potentially relevant, fail to provide strong enough support for the conclusion. The connection between premises and conclusion is too weak to justify the claim being made.
These fallacies violate the principle of sufficiency. Unlike fallacies of relevance (where premises are logically irrelevant), here the premises offer *some* support, but it's inadequate. This section covers common fallacies of weak induction: Appeal to Unqualified Authority, Appeal to Ignorance, Hasty Generalization, False Cause, Slippery Slope, and Weak Analogy.
After completing this section, you will be able to:
What defines the Appeal to Unqualified Authority fallacy?
Arguments often rely on expert testimony or authority. Such arguments (arguments from authority) are inductive and can be strong if the authority cited is indeed a reliable expert in the relevant field.
The Appeal to Unqualified Authority fallacy (Latin: *argumentum ad verecundiam*, "argument to modesty/shame") occurs when the cited authority or witness lacks the appropriate expertise or credibility regarding the conclusion being drawn. The arguer assumes the authority is reliable without sufficient warrant. Common examples include celebrity endorsements for products outside their expertise.
Example:
Famous artist Worku stated that Vera Pasta is the most nutritious food available. Therefore, Vera Pasta must be the most nutritious food.
This argument commits the fallacy because Artist Worku, while perhaps an expert in art, is presented as an authority on nutrition, a field in which he likely lacks expertise. His opinion on pasta nutrition is unreliable evidence.
A subtler version occurs when an expert in one field makes pronouncements about another, possibly related, field where they lack specific expertise.
Example:
Professor Kebede, a renowned expert in animal genetics, argues that complex societies inevitably exhibit higher levels of labor division compared to simpler societies.
While Professor Kebede is an expert in genetics, the conclusion drawn is sociological. His expertise in biology doesn't automatically qualify him as an authority on social structures, making the appeal potentially fallacious.
Furthermore, appealing to authority in highly controversial fields (like religion or morality) where experts themselves disagree is often problematic. If there's no consensus or objective way to determine which authority is correct, citing one expert provides weak support for a definitive conclusion.
What defines the Appeal to Ignorance fallacy?
The Appeal to Ignorance fallacy (Latin: *argumentum ad ignorantiam*) occurs when premises state that nothing has been proven one way or the other about a particular claim, and the conclusion then makes a definite assertion (either positive or negative) about that claim. Essentially, it argues that because something hasn't been proven false, it must be true, or because it hasn't been proven true, it must be false.
Examples:
People have tried for centuries to provide conclusive evidence that Haile Selassie I of Ethiopia was a descendant of King Solomon of Israel, and no one has ever succeeded. Therefore, we must conclude that Haile Selassie I was *not* a descendant of King Solomon.
Conversely: People have tried for centuries to *disprove* the claim that Haile Selassie I was a descendant of King Solomon, and no one has ever succeeded. Therefore, we must conclude that Haile Selassie I *was* in fact a descendant of King Solomon.
These arguments are typically fallacious because a lack of proof (ignorance) does not constitute proof of the opposite. The premises report a failure to find evidence, which is not positive evidence *for* or *against* the claim itself. The premises offer insufficient grounds for the definitive conclusion drawn.
Exception 1: Exhaustive Investigation. If qualified experts conduct a thorough investigation within their field and fail to find any evidence of a phenomenon's existence, this *can* constitute positive evidence *against* its existence.
Example (Potentially Non-Fallacious):
Teams of historians have meticulously searched for evidence disproving the claim that Emperor Tewodros II committed suicide at Maqdala but have found none. Given the extensive research, we can reasonably conclude he did commit suicide.
If the investigation was truly exhaustive by qualified experts, the lack of contrary evidence lends significant probabilistic support to the conclusion.
The second major exception involves legal procedures where a presumption exists. In many legal systems (including Ethiopia, notionally), a person is presumed innocent until proven guilty.
Example (Non-Fallacious Legal Argument):
Members of the jury, the prosecution has presented its case against the defendant. However, they have failed to prove guilt beyond a reasonable doubt. Therefore, under the law, the defendant is not guilty.
This argument does not commit the fallacy. "Not guilty" in this legal context specifically *means* that guilt beyond a reasonable doubt was not proven. The conclusion follows directly from the premise about the prosecution's failure, given the legal standard of presumed innocence. It doesn't claim the defendant *factually* didn't commit the crime, only that the standard for legal conviction was not met.
What defines the Hasty Generalization fallacy?
Hasty Generalization (also known as Converse Accident) is a fallacy affecting inductive generalizations. An inductive generalization draws a conclusion about an entire group or population based on observing a sample of that group. The fallacy occurs when the sample observed is too small or biased (not representative) to reliably support the conclusion drawn about the whole group.
For example, concluding that 80% of university students favor a policy based on polling only 10% is a standard inductive generalization. Its strength depends on whether the 10% sample accurately represents the entire student body.
The key issue in generalizations is whether the sample is representative (accurately reflects the characteristics of the population) or biased. Factors determining representativeness include:
The Hasty Generalization fallacy occurs when there's a significant likelihood the sample isn't representative, usually because it's too small or clearly biased.
Example:
Addis Zemen newspaper interviewed ten young people about their reading habits and found none had read a book in the past two years. The conclusion is obvious: young people in Ethiopia no longer have a culture of reading books.
This argument commits hasty generalization. A sample of ten young people is far too small and likely unrepresentative to support such a sweeping conclusion about *all* young people in the country.
Hasty Generalization can sometimes be confused with the fallacy of Composition, especially when dealing with classes and their members.
To distinguish: Examine the conclusion. If it makes a claim about each individual member of a class (e.g., "All students are X"), it's a generalization (potentially hasty). If it makes a claim about the class as a whole (e.g., "The student body is Y"), it relates to composition.
Example Distinction: "Fleas are small" (General statement - distributive). "Fleas are numerous" (Class statement - collective).
What defines the False Cause fallacy?
The False Cause fallacy occurs when the link between premises and conclusion depends on an imagined or insufficiently supported causal connection that probably doesn't exist or is misrepresented. Arguments about cause and effect (causal inferences) reason from cause to effect or effect to cause.
Establishing causality rigorously is complex. Evidence often relies on statistical correlation: event A and event B frequently occur together. However, correlation does not automatically imply causation.
Leaping from correlation to causation can be fallacious due to several issues:
Example (Potential Coincidence/Common Cause):
A study found a correlation between military spending (% of GNP) and infant mortality rates across 141 countries. The researchers suggested a causal link.
Critics questioned this, noting similar correlations could be found with irrelevant factors (like banana consumption). The correlation might be coincidental or due to common underlying factors (e.g., poverty, lack of development) causing *both* high military spending *and* high infant mortality.
Example (Potential Common Cause):
Studies reported at a conference showed correlations between pet ownership and positive traits like lower blood pressure, better survival odds after heart attacks, higher self-reliance in women, better social skills in men, and greater empathy in children. Researchers suggested pets cause these benefits.
While the correlation might be real, the conclusion that pets *cause* these benefits might commit a false cause fallacy. An alternative explanation (a common cause) is that people with pre-existing positive social qualities, better health habits, or more stable lives might be more likely to acquire and maintain pets *and* exhibit these positive outcomes independently. The pet ownership and positive outcomes could both stem from underlying personality or lifestyle factors.
While arguments from correlation can be useful, critical evaluation is needed. The False Cause fallacy occurs when an argument relies on a questionable causal connection. Key varieties include:
Example (Post Hoc Ergo Propter Hoc):
Since I came into office two years ago, the rate of violent crime has decreased significantly. So, it is clear that the longer prison sentences we implemented are working.
This argument assumes the longer sentences *caused* the crime decrease simply because they came first. This commits the post hoc fallacy. While the sentences *might* be a factor, other potential causes (improved economy, demographic shifts, increased policing, etc.) are ignored. Temporal sequence alone doesn't establish causality.
The Oversimplified Cause fallacy occurs when an effect likely results from multiple causes, but the arguer selects just one (often convenient or self-serving) and presents it as the sole or primary cause, ignoring other contributing factors.
Example:
University entrance exam scores have been dropping for years. What's the reason? During this same period, students' daily time spent on Facebook has increased dramatically. The cause is obvious: students are wasting time on social media instead of studying.
Increased Facebook time might contribute to lower scores, but claiming it's the *sole* or *obvious* cause oversimplifies a complex issue. Other factors like changes in curriculum, teaching methods, socioeconomic factors, or decreased parental involvement could also play significant roles. Blaming only Facebook ignores these other potential causes.
The Oversimplified Cause fallacy is often driven by self-serving motives: taking undeserved credit for positive outcomes, blaming opponents for negative ones, or shifting responsibility onto a convenient scapegoat.
This fallacy differs from pure post hoc or non causa pro causa in that the selected factor might actually be *a* contributing cause, but its significance is exaggerated by presenting it as the *only* or *main* cause, suppressing the complexity of the situation. Critical thinking demands acknowledging multiple contributing factors when appropriate.
What defines the Slippery Slope fallacy?
The Slippery Slope fallacy is a specific type of flawed argument from negative consequences. It occurs when the conclusion of an argument rests upon an alleged chain reaction of causes and effects, where there is insufficient reason to believe that the chain reaction will actually occur.
Arguments from consequences themselves are common and often legitimate: "Action A is bad because it will lead to negative consequence B." The slippery slope variant argues against an initial action (A) by claiming it will inevitably trigger a sequence of events (A → B → C → ... → Z), ultimately leading to some disastrous final outcome (Z). The fallacy occurs when the links in this claimed chain reaction are weak or unsubstantiated.
The core idea of a slippery slope argument is that taking the first step makes subsequent steps increasingly likely or unavoidable, like sliding down a steep, slippery hill. Once started, the progression towards the undesirable outcome seems inevitable. The warning is: avoid the first step to prevent the entire chain reaction.
While some chain reactions are plausible, the slippery slope *fallacy* occurs when the arguer asserts such a sequence without providing sufficient evidence for the causal links between the steps. The connection between one step and the next is often assumed rather than demonstrated.
Example:
We must oppose the authorization of the donkey slaughterhouse in Bishoftu! If this is allowed, workers there will start eating donkey meat, violating cultural norms. Then their families will start, then their neighbors. Soon, the entire country will abandon its traditional food culture, leading to societal collapse!
This argument presents a chain reaction (slaughterhouse → workers eating → families eating → neighbors eating → national culture collapse) triggered by the initial action. However, the causal links are highly speculative and lack strong evidence. It's unlikely that allowing a specific abattoir would inevitably lead to such a drastic nationwide cultural shift. The argument relies on an unsupported, fear-inducing chain reaction, thus committing the slippery slope fallacy.
Slippery slope arguments are essentially a type of false cause fallacy, focusing on a dubious chain of causes. Identifying the fallacy can be tricky if the likelihood of the chain reaction is genuinely uncertain.
However, many fallacious slippery slopes rely more on emotional appeal (fear of the dire outcome) than on evidence for the causal links. The arguer assumes the bad outcome will follow from the initial step and uses this fear to persuade, without demonstrating the probability of each step in the chain. When an argument predicts a dire chain reaction based primarily on emotional conviction rather than evidence, it's likely committing the slippery slope fallacy.
What defines the Weak Analogy fallacy?
The Weak Analogy fallacy affects arguments from analogy. An argument from analogy reasons that because two things (or situations) are similar in certain known respects, they are likely similar in some further, unknown respect.
The strength of an argument from analogy depends heavily on the *relevance* and *degree* of similarity between the two things being compared, especially concerning the property being inferred. While two things might share some similarities, they will also have differences. The fallacy of weak analogy occurs when the similarities cited are not relevant or strong enough to support the conclusion drawn.
Example (Potentially Strong Analogy):
Substance Alpha caused genetic abnormalities in white mice after daily ingestion for 90 days. Since mice and humans share many biological similarities (being mammals, similar metabolic processes), Substance Alpha will probably also cause genetic abnormalities in humans under similar exposure.
This analogy might be considered strong (though still inductive) because the similarities cited (mammalian biology, metabolism) are relevant to how a substance might affect genetics.
Evaluating analogical arguments involves: (1) Identifying shared attributes between the entities being compared (A and B). (2) Determining if the inferred attribute (z) is causally or systematically related to those shared attributes (a, b, c...). If there's a relevant systematic connection, the analogy is stronger; if the connection is superficial or irrelevant, the analogy is weak.
Example (Weak Analogy):
When an individual is diagnosed with cancer, doctors strive to eliminate the cancerous growth through surgery, radiation, or chemotherapy. Murderers and kidnappers are like cancerous growths on society. Therefore, these criminals, once convicted, should be eliminated through capital punishment, just like cancer.
This argument commits the fallacy of weak analogy. It compares criminals in society to cancerous cells in a body. While both might be considered harmful "growths," the analogy breaks down because the relevant properties differ significantly. Cancer cells cannot be rehabilitated; eliminating them is often the only option. Human criminals, however, are complex beings within a social system; options like rehabilitation, education, and addressing root causes exist. Treating criminals exactly like cancer cells ignores crucial differences, making the analogy too weak to support the conclusion about capital punishment.
Fallacies of Presumption arise because the premises presume (assume) what they purport to prove, rather than providing independent support. These fallacies don't necessarily suffer from irrelevant premises or insufficient evidence in the same way as the previous categories. Instead, the problem lies in an unjustified assumption embedded within the argument's starting point. Key fallacies in this group include Begging the Question, Complex Question, False Dichotomy, and Suppressed Evidence.
After completing this section, you will be able to:
What defines the Begging the Question fallacy?
The fallacy of Begging the Question (Latin: *petitio principii*, "request for the source/principle") occurs when an arguer uses premises that assume the truth of the conclusion they are supposed to be proving. Instead of providing independent evidence, the argument essentially circles back to its starting point, creating an illusion of support where none exists. This can happen in several ways: leaving out a key (and questionable) premise, restating the conclusion as a premise in different words, or reasoning in a circle.
The most common form involves omitting a crucial, potentially false or debatable premise, making the stated premise seem sufficient when it isn't.
Examples:
Murder is morally wrong. This being the case, it follows that abortion is morally wrong.
Of course humans and apes evolved from common ancestors. Just look how similar they are.
It’s obvious that the poor in this country should be given government handouts. After all, these people earn far less than the average citizen.
Clearly, terminally ill patients have a right to doctor-assisted suicide. After all, many cannot commit suicide by themselves.
These arguments "beg" (evade) crucial questions:
The missing premises are the controversial points that need support. By omitting them and using confident phrasing ("of course," "clearly"), the arguer creates an illusion that the stated premise adequately supports the conclusion. The argument fails because it assumes the very point it needs to prove.
This form of begging the question is common in arguments about religion or other deeply held beliefs:
The world displays amazing organization. Obviously, this world was created by an intelligent God.
This argument begs the question: Does the observed organization *necessarily* imply creation by an intelligent God, or could there be other explanations (e.g., natural processes)? The argument assumes the link it needs to establish. While the conclusion might be true, the argument itself offers no independent proof, mainly reinforcing pre-existing beliefs.
A second form of begging the question occurs when the conclusion simply restates a possibly false premise in different words. The premise and conclusion are logically equivalent, offering no independent support.
Examples:
Capital punishment is justified for crimes like murder and kidnapping because it is quite legitimate and appropriate that someone be put to death for committing such hateful acts.
(Here, "justified" means essentially the same as "legitimate and appropriate.")
Anyone who preaches revolution must have a vision of the future, for the simple reason that if a person has no vision of the future, they could not possibly preach revolution.
(Premise and conclusion state the same condition).
By rephrasing, the arguer creates an illusion of providing evidence, but the argument merely spins its wheels, assuming the point it's trying to prove ("How do you know capital punishment *is* legitimate?").
What defines the Complex Question fallacy?
The Complex Question fallacy occurs when two or more questions are disguised as a single question, requiring a single answer that implicitly affirms a presumed condition or assumption embedded within the question. Answering the complex question directly (e.g., with "yes" or "no") traps the respondent into conceding the hidden assumption.
Classic Examples:
Have you stopped cheating on exams?
(Presumes the respondent *has* cheated in the past).
Where did you hide the stolen money?
(Presumes the respondent *did* steal money).
These are not simple requests for information but attempts to trick the respondent into an implicit admission.
Consider the question: "Have you stopped cheating on exams?"
• If the respondent answers "Yes," the implied argument is: "You said 'yes' to having stopped cheating, therefore you admit you cheated in the past."
• If the respondent answers "No," the implied argument is: "You said 'no' to having stopped cheating, therefore you admit you are still cheating."
Similarly, for "Where did you hide the stolen money?":
• Answering "Under the bed" implies: "You stated where you hid the money, therefore you admit you stole it."
• Answering "Nowhere" could imply: "You said you hid it nowhere, therefore you must have already spent or destroyed it."
Each complex question actually contains multiple implicit questions. "Have you stopped cheating?" bundles:
1. Did you cheat in the past?
2. If yes, have you stopped now?
The correct way to handle a complex question is not to answer it directly but to divide it into its component parts and address each separately, particularly challenging the embedded presupposition if it's false (e.g., "I never cheated in the first place").
Note on Leading Questions: Complex questions differ from leading questions (common in legal settings), which suggest the desired answer but don't necessarily embed a false presupposition to trap the respondent. Example: "Didn't you see the defendant run the red light?" (Suggests a "yes" answer). Leading questions might be disallowed in certain legal contexts but aren't inherently logical fallacies like complex questions.
What defines the False Dichotomy fallacy?
The False Dichotomy fallacy (also called False Dilemma or Either-Or Fallacy) occurs when an argument presents two alternatives in a disjunctive ("Either A or B") premise as if they are the *only* possible options, when in fact other alternatives exist. The argument then typically eliminates one of the presented options, leaving the other as the supposedly necessary conclusion.
While the argument form (Disjunctive Syllogism: Either A or B; Not B; Therefore A) is valid, the fallacy lies in the *falsity* of the disjunctive premise, which incorrectly presents the options as exhaustive.
Examples:
Example 1: Either classical democracy originated solely from the Gada System or solely from Athens. Since historical evidence shows influences beyond Athens, it must have originated solely from the Gada System.
(Problem: Assumes these are the only two options, ignoring other potential origins or combined influences).
Example 2: Either you buy me this new car, or we're getting divorced. You don't want a divorce, do you? Therefore, you must buy me the car.
(Problem: Presents only two extreme options, ignoring possibilities like negotiation, compromise, or not buying the car *without* getting divorced).
Example 3: Either you fully support the government's new policy, or you are unpatriotic. You claim to be patriotic. Therefore, you must fully support the new policy.
(Problem: Ignores the possibility of being patriotic while disagreeing with specific policies).
In each case, the "Either...or..." premise falsely excludes other relevant possibilities.
The fallacy occurs because the disjunctive premise is presented as if it covers all possibilities (is exhaustive) when it doesn't. A legitimate disjunction *does* cover all possibilities (e.g., "Either the number is even, or it is odd").
In a false dichotomy, the presented alternatives are often extremes, ignoring middle ground or other options, making the "Either...or..." premise false or highly questionable. The argument then uses a valid structure (disjunctive syllogism) but starts from a false premise, rendering it unsound.
Example (Valid Disjunctive Syllogism - Not False Dichotomy):
Either Abay River is entirely within Ethiopia or it is not entirely within Ethiopia. (True Dichotomy)
Abay River is not entirely within Ethiopia (it flows into Sudan).
Therefore, the statement "Abay River is entirely within Ethiopia" is false.
The False Dichotomy fallacy often involves only stating the flawed "Either...or..." premise, implicitly inviting the listener to eliminate one option.
What defines the Suppressed Evidence fallacy?
Recall that a cogent inductive argument must be strong and have all true premises, including the requirement that the premises consider all relevant evidence (the total evidence requirement). The Suppressed Evidence fallacy occurs when an arguer intentionally or unintentionally ignores or omits crucial evidence that undermines the conclusion drawn from the stated premises. The argument presents evidence supporting the conclusion but fails to mention important counterevidence.
Example:
Investing in Somalia seems promising for several reasons: raw materials are cheap, labor costs are low, there's a potential market for our product, and access to a port facilitates exports. Therefore, we should strongly consider investing in Somalia.
This argument commits the suppressed evidence fallacy if the arguer knowingly ignores crucial negative factors, such as political instability, lack of security, or inadequate infrastructure in Somalia, which would significantly outweigh the positive factors mentioned and likely lead to a different conclusion about investment viability.
This fallacy falls under presumption because it creates the false presumption that the presented evidence is complete and sufficient, when in fact it is not.
Suppressed evidence is extremely common in advertising. Advertisements naturally highlight positive features while omitting negative ones (e.g., high costs, health risks, poor durability). Drawing conclusions based solely on advertising often involves committing this fallacy.
Example:
The advertisement for Kentucky Fried Chicken says, “Buy a bucket of chicken and have a barrel of fun!” Therefore, if we buy that chicken, we are guaranteed to have lots of fun.
The argument ignores suppressed evidence: the fun isn't included with the chicken; the chicken might be unhealthy (high in fat); potential weight gain might not be fun. Relying only on the ad's claim leads to a fallacious conclusion.
Another form involves ignoring significant events or changes over time that render past trends or evidence less relevant to future predictions.
Example:
During the past fifty years, Poland generally experienced a low standard of living. Therefore, Poland will probably continue to have a low standard of living for the next fifty years.
This argument suppresses crucial evidence: Poland's political and economic situation changed dramatically after the collapse of the Soviet bloc. Its past standard of living under a different system is not necessarily indicative of its future trajectory under a market economy. Ignoring this major change makes the argument fallacious.
Quoting passages out of context from authoritative sources (like religious texts or legal documents) to support a conclusion the original text didn't intend is another form of suppressing evidence. The omitted context changes the meaning.
Example (Simplified):
The Second Amendment to the U.S. Constitution states "the right of the people to keep and bear Arms, shall not be infringed." Therefore, any law controlling handguns is unconstitutional.
This argument suppresses the amendment's preceding clause: "A well regulated Militia, being necessary to the security of a free State..." By omitting this context, the argument ignores the potential interpretation that the right relates specifically to maintaining a militia, not an unrestricted individual right. Presenting only part of the text suppresses evidence relevant to its interpretation.
This final category covers fallacies arising from linguistic issues. Fallacies of Ambiguity (Equivocation, Amphiboly) occur when an argument's conclusion depends on exploiting the ambiguity of a word, phrase, or sentence structure.
Fallacies of Grammatical Analogy (Composition, Division) occur when an argument incorrectly transfers an attribute between parts and the whole (or vice versa), often because its grammatical structure resembles that of a valid argument where such transference *is* legitimate. This section examines these four fallacies related to language structure and meaning.
After completing this section, you will be able to:
How does the principle of clarity relate to fallacies of ambiguity?
Fallacies of ambiguity arise from unclear language. An expression is ambiguous if it can have multiple distinct interpretations in context. When an argument's conclusion relies on illicitly shifting between these meanings or misinterpreting an ambiguous statement, a fallacy of ambiguity is committed. These violate the standard of clarity crucial for logical reasoning.
What defines the fallacy of Equivocation?
The fallacy of Equivocation occurs when the conclusion depends on a single word or phrase being used with two different meanings (senses) within the same argument. The shift in meaning makes the argument appear valid or sound when it isn't.
Examples:
Some triangles are obtuse [having an angle > 90°]. Whatever is obtuse [dull/stupid] is ignorant. Therefore, some triangles are ignorant.
Any law [statutory rule] can be repealed by the legislative authority. But the law of gravity is a law [natural principle]. Therefore, the law of gravity can be repealed by the legislative authority.
We have a duty to do what is right [morally correct]. We have a right [just claim/entitlement] to speak out in defence of the innocent. Therefore, we have a duty to speak out in defence of the innocent.
In the first example, "obtuse" shifts meaning from a geometric term to a term describing mental capacity. In the second, "law" shifts from statutory law to natural law. In the third, "right" shifts from meaning "morally correct action" to "entitlement/claim."
Equivocation is most deceptive when the two meanings are subtly related or when the shift occurs over a lengthy argument, making it harder to detect. Political discourse often uses terms like "freedom," "equality," or "security" equivocally. Identifying equivocation requires careful attention to how key terms are used throughout an argument.
What defines the fallacy of Amphiboly?
The fallacy of Amphiboly occurs when an arguer misinterprets an ambiguous statement (due to grammar, punctuation, or awkward phrasing) and draws a conclusion based on that faulty interpretation. The ambiguity lies in the sentence structure (syntax), not usually in a single word's meaning. Typically, the ambiguous statement is made by someone other than the arguer committing the fallacy.
Common causes include dangling modifiers, unclear pronoun antecedents, or ambiguous word arrangements.
Examples:
The tour guide said that standing in Meskel Square, the new federal police building could easily be seen. It follows that the new federal police building is located in Meskel Square.
(Ambiguity: Who or what is standing in Meskel Square? The observer or the building? The conclusion assumes the building.)
Habtom told Megersa that he had made a mistake. It follows that Habtom has the courage to admit his own mistakes.
(Ambiguity: Whose mistake? "He" could refer to Habtom or Megersa. The conclusion assumes "he" refers to Habtom.)
These ambiguities arise from sentence structure (syntax), leading to misinterpretation.
Amphiboly can cause serious issues in legal documents like contracts and wills, where ambiguous phrasing leads to conflicting interpretations and disputes.
Example (Ambiguous Will):
Mrs. Zenebu stated in her will: “I leave my house and my clothes to Lemma and Mengistu.” Lemma argues from this: Therefore, I (Lemma) get the house, and Mengistu gets the clothes.
This conclusion arises from one interpretation of the ambiguous phrasing. Mengistu could plausibly argue for another interpretation (e.g., that both assets should be shared equally). The ambiguity could have been avoided with clearer wording (e.g., adding "respectively" or "to be shared equally").
Key Differences:
While distinct, the two fallacies can sometimes occur together if syntactical ambiguity also involves a word with multiple meanings relevant to the different interpretations.
Example (Combined):
The cookbook recommends serving the oysters when thoroughly stewed. Apparently, the delicate flavor is enhanced by the intoxicated condition of the diners.
This involves amphiboly (is "stewed" modifying oysters or diners?) and potential equivocation ("stewed" meaning cooked vs. intoxicated).
This subgroup includes fallacies where an argument appears structurally sound because its grammar resembles that of legitimate arguments, but the resemblance is misleading. The argument improperly transfers attributes due to this superficial grammatical similarity. The two main fallacies here are Composition and Division.
What defines the fallacy of Composition?
The fallacy of Composition occurs when an argument erroneously transfers an attribute from the *parts* of something onto the *whole*. It incorrectly assumes that because the parts have a certain property, the whole entity must also have that property.
Examples (Fallacious):
Each player on this basketball team is an excellent athlete. Therefore, the team as a whole is excellent.
(Problem: Excellent individual players don't guarantee excellent teamwork).
Each atom in this piece of chalk is invisible to the naked eye. Therefore, this piece of chalk is invisible to the naked eye.
(Problem: Properties of micro-parts don't always apply to the macro-whole).
Sodium and chlorine atoms are, individually, dangerous. Therefore, sodium chloride (table salt) must be dangerous.
(Problem: Chemical compounds have properties different from their constituent elements).
The transference of the attribute (excellence, invisibility, dangerousness) from parts to whole is illegitimate in these cases.
However, not all part-to-whole transferences are fallacious. Sometimes, the whole *does* possess the attribute precisely because the parts do.
Examples (Non-Fallacious):
Every atom in this piece of chalk has mass. Therefore, the piece of chalk has mass.
(Legitimate: Mass is additive).
Every component part of this machine is made of metal. Therefore, the entire machine is made of metal.
(Legitimate: Assuming "machine" refers only to its components).
Distinguishing fallacious composition from legitimate transference depends on the specific attribute and the relationship between parts and whole.
Confusion between Composition and Hasty Generalization can arise when the "whole" is a class and the "parts" are its members.
Recall the distinction between collective and distributive predication:
Distributive: Fleas are small. (Each flea is small).
Collective: Fleas are numerous. (The class of fleas is large).
To differentiate:
Example: "Each member of the team is talented, therefore the team is talented." Conclusion is about the team as a whole (collective) -> potential Composition. Vs. "Some members of the team are tall, therefore all members of the team are tall." Conclusion is about each member (distributive) -> potential Hasty Generalization.
What defines the fallacy of Division?
The fallacy of Division is the reverse of Composition. It occurs when an argument erroneously transfers an attribute from a *whole* (or a class) onto its *parts* (or members). It incorrectly assumes that because the whole has a certain property, each part or member must also have that property.
Examples (Fallacious):
Salt is a non-poisonous compound. Therefore, its component elements, sodium and chlorine, must be non-poisonous.
(Problem: Compound properties don't always transfer to elements).
The Royal Society is over 300 years old. General Merid Hussein is a member of the Royal Society. Therefore, General Merid Hussein must be over 300 years old.
(Problem: Attributes of an organization (age) don't transfer to individual members).
This machine is heavy. Therefore, all the parts of this machine must be heavy.
(Problem: Light parts can make a heavy whole).
The transference of the attribute (non-poisonous, age, heaviness) from whole to part is illegitimate here.
Like composition, division is not always fallacious. Some attributes *do* transfer legitimately from whole to parts.
Example (Non-Fallacious):
This piece of chalk has mass. Therefore, the atoms composing this piece of chalk have mass.
(Legitimate: Mass applies at both levels).
This puzzle is rectangular. Therefore, the pieces of this puzzle are rectangular.
(Likely fallacious: puzzle pieces are rarely the same shape as the whole puzzle).
Distinguishing Division from Accident: Confusion can arise when the "whole" is a class.
To distinguish: Examine the premise about the whole/group. If it's a class statement (collective predication), the potential fallacy is Division. If it's a general statement (distributive predication), the potential fallacy is Accident.
A fallacy is an error in reasoning or argumentation that stems from factors other than merely false premises, often involving logical defects or illusions of validity. Fallacies are broadly categorized as formal or informal. Formal fallacies involve structural errors detectable by analyzing argument form (affecting only deductive arguments). Informal fallacies involve errors in content, context, or language, requiring analysis beyond mere structure (affecting both deductive and inductive arguments).
Fallacies of Relevance occur when premises are logically irrelevant to the conclusion, often relying on emotional appeals (force, pity, popular sentiment) or personal attacks (ad hominem) instead of evidence. Misapplying general rules (Accident), distorting arguments (Straw Man), drawing irrelevant conclusions (Missing the Point), or diverting attention (Red Herring) also fall here. Fallacies of Weak Induction occur when relevant premises provide insufficient support for the conclusion, such as appealing to unqualified authorities, arguing from ignorance, making hasty generalizations from poor samples, assuming false causal links, positing unlikely chain reactions (Slippery Slope), or relying on poor analogies.
Fallacies of Presumption occur when arguments assume what they need to prove. This includes Begging the Question (circular reasoning or assuming a key premise), Complex Question (embedding assumptions in questions), False Dichotomy (presenting limited options as exhaustive), and Suppressed Evidence (ignoring crucial counterevidence).
Fallacies of Ambiguity arise from unclear language. Equivocation exploits shifts in word meaning, while Amphiboly exploits ambiguous sentence structure.
Fallacies of Grammatical Analogy mimic the structure of valid arguments but involve illegitimate transference of attributes. Composition wrongly transfers attributes from parts to whole, while Division wrongly transfers attributes from whole to parts. Recognizing these various fallacies is crucial for evaluating arguments effectively and avoiding errors in one's own reasoning.