| Fallacy | Description | Why is this wrong? | Diagnosis / proof | Comments / Examples |
| Ad-Hominem
Ad Hominem arguments seek to discredit a claim by attacking the person making the claim. This is one of the most common forms of fallacious argument on Usenet. |
Ad-Hominem Circumstantial
| This may take the form: A makes this claim, but it is in A's interests to claim it, therefore it is false". A's circumstances are represented as having a bearing on the validity of the claim. | The fact of A having an interest in making the claim does not make it false. | Identify whether A's interest is a material fact; review the source data. | "Well you would say that, wouldn't you?"
A cigarette scientist saying smoking is not addictive is grounds for scepticism, Clare Short claiming that we should increase the aid budget may well be right. |
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| A claim is made out to be false because 1) it is inconsistent with something else a the claimant has said or 2) the claim is inconsistent with the claimant's known actions. | 1) even if the claimant makes two inconsistent claims, that does not meant his is the incorrect one (and indeed the change may be a response to new evidence)
2) the fact that actions do not match the claims may or may not be hypocrisy, but it is not evidence either for or against the claims themselves. | Identify the two claims; see if they genuinely are incompatible. Review the development of the argument over time: is new data now available? | "You claim helmets don't save lives, but you wear a helmet yourself!" - identified as tu quoue but actually closer to misdirection, since the there is no evidence that the helmet is being worn in the expectation of saving the wearer's life. |
Personal Attack (basic Ad-Hominem)
| Abusive remarks are substitued for reasoned argument: "The liar X says this, therefore this is wrong"; or, "X says this, but X is not qualified to judge, therefore this is wrong". | Although X may be a pathological liar, and both expertise and past history will rightly inform a person's credibility, this is not in itself an indicator of the merit of claims advanced by X. | Excise the ad-hominem and reprise, then argue, the hard evidence, if any. Remain calm! | Jeffrey Archer claims to be a great novellist, but he has been to prison for lying so how can we believe him? An ad-hominem attack, notwithstanding the merit or otherwise of Archer as a novellist. |
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| X seeks to discredit claims made by Y, by presenting unfavourable information about Y. For example: Y has a criminal record, Y makes claim C, claim C must be wrong because Y said it. | The fallacy is obvious: no evidence is offered regarding the claims themselves.
1) The validity of the claims is not dependent on the stock of the individual making them.
2) The discreditable information may be unrelated to the claims. | Identify whether evidence has been produced to support the claim. Establish whether the unfavourable information is germane. | A special case of appeal to prejudice or genetic fallcy.
"He says we should trust hm, but he is a convicted fraudster" is legitimate; "he says we should support hunting but he is a convicted fraudster" is not. |
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| The style, spelling or grammar of A is said to affect the validity of A's conclusions. | A valid case may be poorly argued, and a poor case well argued. The quality of writing is not indicative of the quality of the evidence. | Identify whether the stylistic issue is germane. | Any spelling or grammar flame fits the bill here, but sometimes a poorly-argued case is indicative of lack of reasoning. |
| Ambiguity
Language is used unclearly, whether deliberately or not. |
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| The same word is used with two different meanings. | | Show that use of the first definition would render the second phrase meaningless, or vice-versa. | A plane is a woodworking tool; a Boeing 737 is a plane, therefore - well, you get the point. |
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| A sentence can be construed in more than one way; the meaning is ambiguous. | | Identify the two possible meanings. | A Usenet favourite: deliberately interpret a phrase one way when it is clearly meant another. Scope for irony. |
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| Emphasis is used to misrepresent the content of a statement. | | Restore the context. | The review: "If you must see this play, take a good book with you". The billboard: "You must see this play" - Reviewer. |
| Appeals to Motives
The category of appeals is a broad one and covers many variations on a common theme, that of persuading the audience to accept a claim at face value by substituting motives for evidence in support for the claim. |
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| An appeal to authority is made when the following steps are followed: X is an authority on this subject; X accepts this claim; therefore this claim is true. | 1) X may not in fact be an authority on the subject (e.g. a causalty doctor may be widely acknowledged as an expert on injuries, but to extend this to claim he is an authority on accidents would be fallacious)
2) there may be a division of informed opinion - and indeed X may be in the minority. | Identify whether the supposed authority's expertise covers the point at issue; establish whether others of similar or greater expertise may disagree. | "Doctors agree that...", well, you can fill in the blanks yourself. The leading helmet promoter in the UK is a nurse who has "seen an awful lot of cycling head injuries" but appears to know little or nothing about causes of cycling crashes. |
Appeal to Anonymous Authority
| In this variant f the above, the authority is not named, making it more difficult to rebut the claim. Thus: "Experts agree..." | Without the identity of the purported experts it is not possible to ascertain whether their expertise is real, or if they are working out of vested interest. | Is the authority identifiable from other data? | Never believe things "overheard in the pub." And maybe it's just me, but I have also become particularly sceptical of advertisements claiming "doctors agree..." |
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| A claim is advanced, and is countered by the threat of rejection. The existence of this threat is then taken as evidence against the claim. | The basis on which the claimant's peers reject the argument is not presented: this is a variant on appeal to authority. | Is the threat of rejection material to the claim itself, or is it an evasive techniquer to avoid harsh truths? | Consider the case of Darwin, threatened with ostracism by his more conservative peers: this threat does not in any way disprove his claims. |
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| The appeal to belief is like the appeal to authority, in that it relies on a claim being believed by others as proof of its correctness, thus: "Most people believe X, therefore X must be true". | The number of people who believe a thing may well be entirely independent of its correctness, especially if they have no expertise in the matter. Not so long ago everybody believed that the world was flat, after all. | Is the belief founded on a common informed judgment? Review the evidence. | This is also known as the "Emperor's new clothes" argument. A classic example is the idea that seat belts save lives. <a href="risk">As Adams found</a>, there is no country in the world where seat belt legislation produced a measurable reduction in road fatalities, yet the first mention of this fact in almost any forum will be met with a mix of hostility and incredulity. |
Appeal to Common Practice
| This takes the form: "X is a common (or majority, or near-universal) action, therefore X is correct (or reasonable or morally justified). | As with most appeals, the existence of even a large body of people prepared to do something is not evidence that the thing is right. | | To say that racial tolerance is the norm and should be required is not itself unreasonable, and this would appear to contradict the fallacy, but here the proof is not in the number of people who follow the practice, but in the nature of the offence which may be given by following counter practice. |
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| 1a) X must be true (false) because if people did not accept X as being true (false) then there would be specified undesirable consequences.
1b) X is true (false) because accepting that X is true (false) has specified beneficial consequences.
2) I wish that X were true (false), therefore X is true (false). This is better described as "wishful thinking." | The consequences of accepting a claim may have no bearing on its correctness. | Show that whether the proposition is true or not does not | This can be simply a way of avoiding an unpleasant truth. This highlights a key difference between rational reasoning and prudential reasoning: rational reasoning is based on evidence, prudential reasoning is based on supporting a desired outcome or state, and is independent of the objective merit of that outcome. |
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| Appeal to Emotion is common in political speeches and advertising, and takes the following form: X makes you feel good or brings you benefit, therefore X is good. | The ability to elicit emotional responses in people, or indeed to show clear benefit to them alone, does not prove a claim; that which makes you feel good can still be wrong. | Is the emotion well-founded? | Peer pressure is an appeal to emotion. |
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| A statement X is presented which is calculated to inspire fear; a statement Y is then made which may be apparently related to X, with the implication that the X will occur if Y is not accepted and acted upon. | 1) There may be no causal relationship between X and Y.
2) The ability to inspire fear does not prove the claim. For example, the feared outcome may be the lesser of two evils. | Show that the threat is not related to the truth or otherwise of the proposition. | Appeal to fear was one way that the appeasement policies of the 1930s were justified: the public was afraid of a second Great War. |
Appeal to Fear: Slippery Slope
| It is asserted that one event must follow from another without any proof of the inevitability of this happening. Often a series of incremenetal steps is proposed. This is generally used as evidence that the first event in the chain should not be allowed to happen. Thus:
If X happens then Y will necessarily happen; Y is undesirable therefore X must be stopped. | Invalid use of the logical "if-then" operator.
No proof is offered that Y follows inevitably from X - even where a plausible mechanism exists. | Identify the proposition which is being argued against; show that the final event in the chain is not a necessary consequence of the proposition - for example, by proving that any one step does not necessarily lead to the next. | "If we let these people in then before we know it there will be a flood-tide of scroungers and terrorists coming in." And so there might, in theory, but we have yet to see any evidence of it: immigration numbers are reducing as the Balkans gradually stabilise, and are in any case less than the reduction in population due to emigration and falling birth rate. |
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| Person A flatters person B, person B wants to believe this flattery so accepts that person A is truthful, person A then makes claim X which person B accepts without question. | No evidence is offered to support the claim. | Is evidence offered? | Often used by politicians on interviewers, with varying success. |
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| X is new, therefore X is better than what went before. | The age of a concept has no bearing on its merit. | Is the novelty of X relevant to its merit? | The Sinclair C5 was novel once :-) |
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| A statement X is presented which is calculated to inspire pity; a statement Y is then made which calls for action based on the emotion elicited by X. | 1) X and Y may have no causal relationship.
2) Y may be the wrong response to X - a better response may exist. | Show that the state of the person pitied has nothing to do with the truth of the proposition. | This is the classic fallacy embodied in cultural differences between the relatively new Western powers and the far more ancient Eastern social systems. And remember: once upon a time the Sinclair C5 was new. |
Appeal to Popularity'' (Ad Populum)
| "Many (most) people approve of X, therefore X is good". A form of appeal to belief sometimes characterised as the "forty billion flies" argument. | As with the appeal to belief, the number of people who approve of a thing may well be entirely independent of its correctness. | Is the widely-held view the result of a common informed judgment, or of widespread ignorance? | The difference between this and the appeal to belief is that in this case people are said to approve of the claim, in the latter they are said to believe it. |
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| The language used embodies the assumption that the listener supports a given proposition: "as any right-thinking person will agree..." | No evidence is offered to support the claim. | | See how many political speeches you can find this in... |
Appeal to Ridicule / Reductio ad Absurdam
| A statement is made which ridicules an idea. This may be by means of extrapolating the idea to its illogical conclusion (reductio ad absurdam). | 1) No evidence is offered that the idea being ridiculed is false.
2) The idea may be valid up to a certain point, but invalid when extrapolated to the claimed extent. | Is evidence offered? If the idea is extrapolated, is the extrapolation both valid and inevitable? | In some ways this is the corollary of the slippery slope fallacy. |
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| "X says this, but X did not support you when you argued for Y, so you should not support X today". | The desire to hurt the person making a claim has no bearing on the validity of that claim. | | |
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| It has always been thus, therefore it cannot be otherwise. | If this were a valid argument then we would still be living in caves. | Is the tradition in and of itself a reason for keeping up the tradition? | Often this can be rebutted by pointing out the date of origin of the tradition - many are newer than people think! - or the reasons why the tradition is no longer valid. |
| Begging the Question | A statement is made, or a question posed, which embodies the claim in its premises. | The claim is introduced by stealth; by accepting the premises of the statement you implicitly accept a claim for which no evidence has been offered. | Identify the premise and whether evidence is advanced elsewhere to support it. | "Given that seat belts save lives, how can compulsion be bad?" - the first phrase begs the question of whether seat belts do, in fact, save lives - and indeed whose lives.
The phrase "begging the question" is often mistakenly used in the sense of inviting the question. |
| Burden of Proof | Proponents of an idea challenge those who are sceptical to prove that the idea is wrong. | 1) The inability of particular sceptics to authoritatively disprove an idea has no bearing on its merit.
2) In science it is generally accepted that you cannot prove a negative. | Identify which side of an argument should rightly carry the burden of proof, and whether the standard of proof is reasonable (e.g. the civil standard of balance of probabilities versus the criminal one of beyond reaosnable doubt). | Helmet sceptics are repeatedly challenged to prove that helmets do not save lives. Why? We are not proposing an intervention. This is not the same as challenging us to refute pro-helmet evidence, which is a reasonable request (and amazingly easy to do in many cases). |
| Complex Question | Unrelated propositions are conjoined in order to slipstream support from one to the other. | Invalid use of the logical "and" operator.
The ideas are not related; support for one neither implies nor depends on support for the other. | Show that it is possible to accept one proposition without accepting the other. | Example: "You should support Freedom and the War on Terror". OK, I'm a liberal, I admit it. |
| Fallacies
A fallacy is, at its most basic, simply a false statement. Here are some of the more common variants: |
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| Important evidence which would undermine a premise is excluded from consideration | | Present the missing evidence. Once may be a mistake, repetition is probably the fallacy of exclusion. | I have been accused in the past of interfering with people making an informed choice by presenting conflicting evidence. Those making this accusation are seeking to employ the fallacy of exclusion. |
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| A statement is presented as fact which is simply wrong. | | The source of all evidence should be cited. | <a href="ASA_Complaint">BeHIT have claimed</a> several times that fifty children die each year of cycling head injuries The real figure is ten; this figure has been widely publicised. |
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| Two or more arguments are presented at least one of which contradicts at least one of the others | | Demonstrate the conflict. | A is longer than B; B is longer than C; C is longer than A. Obviously false - unless you are MC Esher. |
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| On arrival at work I noticed that the receptionist's computer was a Compaq
Therefore all computers at work are Compaq | This is a form of hasty generalisation. A sample of one... | Show that there are examples which contradict the claim. | Stephen refers to this as the "Illicit Major" syllogism: the premise refers to some of a class, the claim to all of that class. |
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| All dogs have four legs
My cat has four legs
Therefore, my cat is a dog | This is a syllogism of four terms (cat, dog, mammal, four legs), and is a special case of equivocation. | Demonstrate the | A classic logical error, and one which is rarely seen these days except with deliberate ironic intent. |
Non-Sequitur: affirming the consequent
| If A is true then B must be true
B is true
Therefore A is true | B may be true, but A may be false - even if A being true would imply B. | Show that a case can exist where A is false and B is true | If I am King then I must be English
I am English
Therefore, I am King. |
Non-Sequitur: denying the antecedent
| If A is true then B must be true
A is not true
Therefore B is false | | Show that a case can exist where A is false and B is true | If I am not English then I cannot be King
I am not King
Therefore, I am not English. |
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| Something must be done
This is something
Therefore this must be done | A satirical view of political reasoning from "Yes, Minister". | | An example of a type of syllogism which Stephen calls "undistributed middle" - in this case "something" is the middle term, and has different meanings in the two statements. |
| Fallacies of Definition |
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| Premises are advanced which cannot coexist. | | | An example of inconsistency. A may be removed after B has been removed, to remove B, first remove C, C is retained by A. As any Mini mechanic will know... |
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| A contains B if it has B in it. B is not defined. | A special case of failure to elucidate | | |
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| The definition is harder to understand than the thing being defined. | | | Often a sign that the person doing the explaining does not understand the subject fully themselves. Not always, I hope, as I am forever falling into this trap. |
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| "I like malt loaf because I am a cyclist." | The underlying premise is untested: this can be a form of begging the question. The reasoning is insufficient. | Identify that the premise is untested; propose tests. | I have not demonstrated that all cyclists like malt loaf, or that my liking is related to my cycling, therefore the explanation is insufficient. |
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| Drivers hate cyclists because they resent them. | The reason for the resentment is not given; therefore the explanation is insufficient. | Identify whether the explanation is complete, or whether further information would be required. | I suppose the standard adult-to-child response of "vecause it is" fits the bill here. |
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| Everybody who filled in the ActiveX questionnaire applet on my website uses Internet Explorer, therefore I need not develop for anythign else. | The evidence cannot show any conclusion other than the desired one. | Show that responses not supporting the pre-existing premise have been excluded. | |
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| An explanation is advanced for a phenomenon, but without showing that the phenomenon exists. | The phenomenon may not exist, therefore the explanation is moot. | | Any explanation for alien abductions would fit this category... |
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| The definition is not sufficiently specific so includes things it should not. | | Enumerate some things which fall inside the definition but should be excluded. | A cat is defined as an animal with four legs (what about dogs?). |
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| The definition is too narrow, so excludes things it should contain. | | Enumerate some things which fall outside the definition but should be included. | A pedal cycle is a two-wheeled, human powered vehicle (what about trikes and yikes?). |
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| An expanation is advanced which does not permit of scientific proof. | | | The existence of God is an untestable hypothesis. Well, until it's too late, anyway. |
| False Generalisations
False generalisations arise when an individual case is assumed ot be representative or indicative of the general case. These are like inductive fallacies but fall short of the appearance of statistical validity. |
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| Dramatic event X has occurred, therefore events of type X are likely. | The drama of an event is no indication of its probability. | | The shroud-wavers' siren call, this is the foundation for calls to spend millions on snow ploughing equipment for areas which see snow once a year and billions on flood defences following a single freak storm. |
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| Claim C is presented; person X says that claim C is not true for him/her; therefore X rejects claim C | 1) X may be wrong in believing that C is not true for them.
2) X may be unrepresentative; C may be generally true.
3) X may be representative, but this does not mean that C is not true for others. | | However vociferously some might protest that they do not take more risks when they feel themselves better protected, the evidence is that the population overall compensates for increases in perceived safety by increased risk taking. Whether the individuals are right or wrong in their case does not change this fact. |
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| X requires action A of others in circumstance C; X is in circumstance C but does not wish action A, therefore X claims to be exempt. | This violates the principle of relevant difference: two individuals should only be treated differently if there is a relevant difference between them. For given values of relevant, of course... | | "I was only a bit over the limit, so I should not be banned, but in general drink-drivers shgould be treated harshly." |
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| Those memers of a class who exhibit a particular property are most commonly featured in the media; therefore, they are rperesentative of that class. | The fallacy is to assume that the characteristics which attract attention are those which define the group. The media has a strong tendency to caricature, especially with "out" groups. | | TV "boffins" are always wacky, zany, with wierd hair / clothing / mannerisms. Most scientists are actually rather ordinary. |
| Gambler's Fallacy | The fact that a trend has departed from its historic course is taken as evidence that it will be reversed shortly. | Although regression to the mean is common, it is not inevitable. | | |
| Genetic Fallacy | The claim is discredited or supported by reference to its origins. | A variation on the appeal to tradition. The origin of a claim is not evidence of its merit or lack of merit. | | |
| Guilt by Association | X says this; you distrust X, therefore this is false. | X's trustworthiness or otherwise is not evidence regarding the merit of any particular thing which X may say. | | |
| Hubris | Overweening pride or arrogance. Not strictly a fallacy, but a source of many, since the speaker is unliekly to test his own conclusions to any degree. | | Is the speaker actually entitled to his pride? | May be combined with an appeal to authority: "I am one of Earth's leading experts on this subject, and I say X, therefore X is true" |
| Inductive or Causal Fallacies
These are fallacies in what is purportedly inductive reasoning (A is true, A implies B, therefore B is true). In each case either A is not true, or A does tno imply B, therefore B is not necessarily true - the existence of a fallacy does not prove that B is false, it simply does not prove that it is true. |
Biased or Unrepresentative Sample
| "X% of people in this subgroup exhibit Y, therefore X% of the population exhibit it." | Without evidence of the sample being statistically representative of the population, the purportedly scientific nature of the claim is irrelevant. | | |
Causation vs. Correlation ''' or '''Common Cause
| A and B are observed together, therefore A and B are related. See also: Post-Hoc. | A and B may appear together due to coincidence or due to some other common cause C, which is not looked for. | | |
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| A and B are share property Y, A exhibits property X, therefore B must exhibit property X. | X is not necessarily related to the property Y shared by A and B - it could be coincidence. | | |
False Categorisation: Composition
| Inferences are made regarding a class or body from the behaviour of its constituents in isolation:
1) "A, B and C, members of a class, all exhibit property X. Therefore all members of the class exhibit X."
2) "All members of the class exhibit proeprty X, therefore the class itself exhibits X". | 1) The sample may be unrepresentative.
2) The whole may behave differently from its consituents.
3) The constituents may behave differently in aggregate than in isolation. | | If you like cheese and you like peas, then you'll love Cheesy Peas! |
False Categorisation: Division
| A corrolary of Composition, the whole exhibits X therefore all constituents of that whole also exhibit X. | 1) The aggregate may not be homogeneous
2) The constituents may behave differently from the aggregate | | |
False Dilemma or False Dichotomy
| Either A or B is true, A is known to be false, therefore B is true. | Invalid use of the logical "or" operator.
1) The choice may not be binary: other options may exist.
2) A and B may not be mutually exclusive as claimed (this may be a form of begging the question). | Show that a third option exists.
Show that A and B are not mutually exclusive. | |
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| A is not known to be false, therefore A is true. | Invalid use of the logical "not" operator.
A is not known - either way. | Show that the proposition may or may not be true, even though only evidence of truth is available. | |
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| A sample is taken and conclusions drawn from it about the whole population, but the sample is too small to be significant. | Closely related to the biased sample fallacy. The individuals observed may not be representative of the whole; the sample is unsufficient to draw the inference. | | "I saw a cyclist ride through a red light, therefore all cyclists ride through red lights." |
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| A is correctly said to cause B, but is insignificant when compared to other causes of B. | The fallacy rests on the argument being used to prioritise the minor cause over the major one; the fact in itself is clearly not fallacious. | Identify other causes, and prove that they are substantially greater. | Mike Vandeman's one-man crusade against mountain biking is founded on this fallacy. Another example might be the danger caused by pavement cycling - it exists, but the numbers killed and injured by motorists on the footway are massively greater. |
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| An argument which purports to prove one thing actually proves another; for example a correct premise may be advanced, and a reason for a proposed remedy, but the remedy does not necessarily match the premise | | Show that the remedy does not match the premise, or that other remedies are possible. | A variant of "Sir Humphrey" |
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| A plausible mechanism exists whereby A might cauise B, therefore A causes B. | 1) No proof is presented that the plausible mechanism actually happens.
2) No attempt is made to find contrary evidence | Is it proven that the supposed mechanism is actually operating, or is it merely advanced as a theory? | This is a core problem with <a href="observational_studies">observational studies</a>; the existence of a plausible mechanism is taken as evidence backing a correlation or biased sample error. |
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| From the Latin post hoc ergo propter hoc, B follows A, therefore A causes B. | Although a sufficient number of examples may be indicative of a causal relationship, they do not prove it. A and B may be consequent from some common cause, but be unrelated to each other, or the apparent consequence may be coincidence | Is there conclusive proof of a causal link? Is a robust mechanism rpoposed? Is there independent evidence in support? | Rife on both sides of the helmet debate; beware of epidemiological studies! |
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| The conclusion of a logical argument is denied. | Whether this is a valid point of view depends on whether the argument is truly logical or whether it contains one or more of these fallacies. | Show the strength of the inference | Sometimes this failing is the result of being wilfully obtuse, sometimes due to the evidence conflicting with cherished beliefs, sometimes the result of someone having dug too big a hole to climb out of easily, and sometimes they are simply putting their fingers in their ears and chanting "la la la la, I'm not listening." Yes, Mr Zaumen, that means you. |
| Middle Ground | A and C are two extreme positions. B is some position which lies between A and C. Therefore, B is correct. | Simply lying between two extreme positions - even centrally between - is not evidence that a position is correct. The truth may lie at or anywhere between the two extremes.
False extremes may be introduced to give a spurious midpoint. | The claim to hold the middle ground may itself be false. Identify the actual extremities of the argument and establish where on that continuum position B lies. Demand evidence in addition to simply not lying at one extreme or the other. | Steven M Scharf plays the "middle ground" fallacy very well, presenting himself as "one of Earth's leading experts" on a variety of subjects, and denouncing his opponents as monomaniacs - yet his consistent refusal to accept that dynamo lights can be adequate for night riding, despite the experience of literally millions of utility cyclists, shows his position to be extreme |
| Proof By Assertion | A statement is made for which no evidential basis is given. | Without evidence no hypothesis, however "obvious", is proven. | | "Of course helmets save lives." |
| Proof By Repetition | An insupportable (e.g. false or unproven) claim is made. The claimant continues to repeat the claim after its insupportability is demonstrated. Eventually the claim may be left unrebutted, and the claimant may then consider it proven. | As Lenin memorably said, a lie told often enough becomes the truth. But only in sociological terms; scientifically it remains a lie. | This is a technique much beloved of Usenet and web forum trolls. The best way to deal with it is to keep calm and point out the fallacy every time. | Anything Mike Vandeman says about mountain biking probably fits the bill here, along with "helmet saved my life" anecdotes. |
| Red Herring | Topic A is under discussion
X introduces topic B and steers debate towards it
Topic A is abandoned
X may claim that because A is no longer in dispute, his version of A is correct. | Changing the topic under discussion does not address the merit of a claim. | Identify the lack of connectedness, if necessary (usually red herrings are inherently obvious). | If you want so see red herringing in their native environment, try arguing about speeding with a motorist, as an "out" cyclist. Within thirty seconds there will be a concerted effort to steer the debate to red light jumping, pavement cycling or some other cyclist infraction. |
| Straw Man | Instead of debating a person's actual views, an exaggerated or distorted version is presented, which is then attacked. | Because the attack is on a distorted version of the position rather than the position itself, the evidence presented does not necessarily apply to the actual position. | Do the arguments advanced actually address the issue (in which case it may simply be irony), or only the distorted form of the issue? | Welcome to Usenet, home of Mr Straw. Characterising helmet sceptics a being anti-helmet is a common straw man. |
| Two Wrongs | A states that an undesirable action against B is necessary in order to prevent B taking similar action against A | 1) A presents no evidence that B intends to take the supposed action.
2) A does not prove that their action is necessary or proportionate (there may be alternatives). | Is the justification in terms of the lesser of two evils (valid), or in terms of retaliatory action? | Killing is wrong. Therefore if you kill, the state will kill you. Er, right. |
