Logical Fallacy
logical fallacy
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What is logical fallacy
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Validity versus truth an argument is valid does not mean the conclusion is true， A valid argument simply means that if the premises are true, the conclusion must be true as well. A sound argument is a valid argument with the additional requirement that the premises (and thus the conclusion) are true. All humans are cows. All cows are plants. All humans are plants. The conclusion is false and the premises are false, this is still a valid argument.
How to avoid logical fallacies
研究方法
研究结果
问题讨论
论文总结
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First, having a good understanding of the Argument Structure and the logical fallacy.
Second, proposing argument relied on wellconducted research, critical thinking and clearly presented facts. Good arguments are not based on emotion, but rather evidence, reason and example.
logical-fallacy
例：“如果是油条，那么是好吃的；面包 Nhomakorabea好吃的；因此面包是油条。”这同样是对直言三段论的误用。
假两难推理
典型形式：“A或B或C；非A；所以B。”
这是对选言三段论的误用。选言三段论的形式是：“A或B；非A；所以B。”，级联起来则是这种形式：“P1或P2或P3……或Pn；非P2且非P3……且非Pn；所以P1。”用福尔摩斯的话说则是：“当排除了所有其它的可能性，还剩一个时，它就是真相，不管它看起来有多么的不可能。”
无效证明
这是一种在证明过程中利用“障眼法”，从而得出错误结论的诡辩手段。
例：证明1是最大的正整数。“假设最大的正整数不是1，而是a，有a > 1；a > 1 > 0，a为正的，所以由a > 1得到a * a > a；但是a * a还是正整数，可是没有任何正整数比a大，矛盾；所以，最大的正整数是1。”（留给各位去揪出“障眼法”之所在。）
目录1简介
2形式逻辑谬误
2.1否定前件谬误2.2肯定后件谬误2.3假两难推理3非形式逻辑谬误
3.1诉诸无知3.2循环论证3.3滑坡谬误3.4以偏概全3.5区群谬误3.6类比失当3.7诉诸公众3.8诉诸恐惧3.9诉诸怜悯3.10假诉诸权威3.11不相干谬误3.12后此谬误3.13无效证明1简介违反思维规律或逻辑规则的议论，尤其是指论证中不符合逻辑的推论。逻辑谬误[1]分为形式逻辑谬误与非形式逻辑谬误。
例：“你是石油公司的员工，你当然要声称全球变暖是假的”
辩论中常常出现的“稻草人”也是该谬误的一种。[2]
后此谬误
又称事后归因、假性因果。仅仅因为A事件先于B事件发生，就断定A事件是B事件的原因。
例：“九点的时候有一只蝴蝶扇动翅膀，十点的时候太平洋上有台风生成，所以蝴蝶扇动翅膀是导致台风生成的原因。”
高英-logic-fallacy-八大逻辑谬误
滑坡谬误
总结词
指论证中假设一个初步行动会导致一系列不太可能的 后续事件，最终导致极端的负面结果。
详细描述
滑坡谬误是一种常见的逻辑谬误，表现为在论证中假 设一个初步行动会导致一系列不太可能的后续事件， 最终导致极端的负面结果。这种谬误的错误在于假设 初步行动必然导致负面结果，而没有提供足够的证据 来支持这一连串的事件必然发生。滑坡谬误常常出现 在政策辩论和商业决策中，由于缺乏足够的证据支持 ，因此这种推理方式并不具有说服力。
间的感受和安排。
假因谬误的案例分析
总结词
假因谬误是指将一个事件视为另一个事件发生的原因，尽管实际上两者并无因果关系。
详细描述
例如，有人认为“自从我开始戴这个护身符，我就没有感冒过”，认为护身符是防止感 冒的原因。但实际上，很可能只是巧合，护身符与不感冒并无因果关系。
倒置因果的案例分析
总结词
倒置因果是指将事件发生的顺序颠倒，错误地认为前一 事件是后一事件的原因。
高英-logicfallacy-八大逻辑谬 误
contents
目录
• 八大逻辑谬误概述 • 形式逻辑谬误 • 非形式逻辑谬误 • 应用与实践 • 案例分析
01
CATALOGUE
八大逻辑谬误概述
定义与特点
定义
逻辑谬误是指论证中存在的逻辑缺陷 或错误，导致论点或结论不可靠。
特点
逻辑谬误通常表现为推理过程中的不 合逻辑或不严谨，可能源于错误的推 理规则或概念使用不当。
要点二
详细描述
以人废言是指因为一个人的身份或观点而否定其言论的价 值或真实性。例如，有人可能会因为某位专家的政治立场 而否定其关于气候变化的观点，或者因为某位作家的性别 而否定其关于性别平等的观点。这种谬误忽略了言论本身 的逻辑和证据价值，而仅仅因为持有某种立场或观点的人 的身份而对其言论进行否定。
Logical Fallacies
Slippery Slope
• Definition: The arguer claims that a sort of chain reaction, usually ending in some dire consequence, will take place, but there's really not enough evidence for that assumption.
Post hoc (false cause)
This fallacy gets its name from the Latin phrase "post hoc, ergo propter hoc," which translates as "after this, therefore, because of this." • Definition: Assuming that because B comes after A, A caused B.
• While guns and hammers do share certain features, these features (having metal parts, being tools, and being potentially useful for violence) are not the ones at stake in deciding whether to restrict guns. Rather, we restrict guns because they can easily be used to kill large numbers of people at a distance. This is a feature hammers do not share--it'd be hard to kill a crowd with a hammer. Thus, the analogy is weak, and so is the argument based on it.
最新Logical Fallacies逻辑谬误
Arguments, like men, are often pretenders. —Plato
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What are fallacies?
Fallacies are defects that weaken arguments. By learning to look for them in your own and others' writing, you can strengthen your ability to evaluate the arguments you make, read, and hear.
Accident
definition
When we apply a generalization to individual cases that it does not properly govern, we commit the fallacy of accident.
Almost every good rule has appropriate exceptions; we argue fallaciously when we reason on the supposition that some rules apply with universal force. Accident is the opposite of false generalization.
Examples
You can’t prove that God exists. Therefore he doesn’t exist. You can’t prove that God doesn’t exist. Therefore he exists. the story of Galileo
阅读练习-Logical Fallacy
Logical Fallacy1.Dicto Simpliciter 绝对判断Definition: It means an argument based on an unqualified generalization.Example: Keeping on a diet can enable people to lose weight. Therefore, if you want to lose weight, you should keep on a diet.2.Hasy Generalization 草率结论Definition: The size of the sample is too small to support the conclusion. It applies a special case to general rule. Or, the premise is obviously not adequate, the person jumps to the conclusion.Example: Fred, the Austrilian, stole my wallet. Thus, all Austrilians are thieves.3.Post Hoc 牵强附会Definition: The cause has no connection with the result. The thing A happens before the thing B in terms of time, but it doesn’t mean that the thing A happening prior is the cause of the thing B happening later.Example: Most young criminals watch violent movies before they commit their crimes; obviously, violent movies lead to juvenile deliquency.4.Contradictory Promises 矛盾前提Definition: The premise and the conclusion contradict each other, so there can be no conclusion.Example: If God can do everything, can he make a stone so heavy that he can’t carry?5.Ad Misericordiam 文不对题Definition: The theme is inconsistent, and the context is irrelevant. An argument based on an appeal to the emotions, like pity or sympathy. Also known as argumentum ad misericordiam or appeal to pity or misery.Example: Maybe he isn’t qualified enough for this job, but think about his relationships, his uncle is the mayor, and his father is the chairman of the company which has steady business relations with us.6.False Analogy 错误类比Definition: Many arguments rely on an analogy between two or more objects, ideas, or situations. If the things that are being compared are really alike in the relevant respects, the analogy is the weak one. Or, the conclusion and the premise happen not in the same situation.Example: Mind and rivers, can be both broad. It is a known fact that the broader the river, the shallower it is. Therefore, it is must be true that the broader the mind is, the shallower it is.7.Hypothesis Contrary to Fact 虚假假设Definition: The hypothesis is contradictory to the reality. It is falsely believedthat there is only one possibility to the state of affairs.Example: If the gunpowder hadn’t been invented, there wouldn’t have been so many wars in the worlds.8.Poisoning the Well 井下投毒Definition: Or speaking “against the man”. The premises may only make a personal attack on the person, instead of offering reasons to show why what he says is false. It is a special case of argumentum ad hominem（人身攻击）.Example: The defendant killed the victim cruelly, I suggest Lord sentence him to guilty.。
Logical_Fallacies逻辑谬误
Examples
President Jones raised taxes, and then the rate of violent crime went up. Jones is responsible for the rise in crime.
The increase in taxes might or might not be one factor in the rising crime rates, but the argument hasn't shown us that one caused the other.
Notice that in the previous example, the more modest conclusion "Some philosophy classes are hard for some students" would not be a hasty generalization.
Two persons’ experiences are, in this case, not enough on which to base a conclusion.
Smoking causes cancer because my father was a smoker and he died of lung cancer.
two special notes about fallacies
Fallacious arguments are very, very common and can be quite persuasive, at least to the casual reader or listener. You can find dozens of examples of fallacious reasoning in newspapers, advertisements, and other sources. There are many different kinds of fallacies with different names.
高英logicfallacy八大逻辑谬误
The cause has no connection with the result.
原因和结果没有必然联系
Contradictory premises 矛盾前提
He decided to give up all his decisions.
No!
When the premises of an argument contradict
No!
Making an analogy between different things.
Hypothesis contrary to fact
与事实相反的假设
If I had studied harder, I would definitely have passed that test .
No!
Exercise is good，so everybody should exercise.
It means an argument based on an unqualified generalization.
即将普遍规则运用于有特殊情况发生 的个别情形之中。
Hasty generalization 草率结论
It applies a special case to general rule.
由个别情形来推断普遍规则.
Post hoc 牵强附会
McDonald's and KFC offer foods with little nutrition, and thus we cannot expect any fast food restaurant to provide us with nutritious foods.
Eight Types of Fallacy
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●Dicto Simpliciter 绝对判断(Latin: "from a maxim without qualification", meaning "from a universal rule") or ad dictum simpliciter (Latin: "to a maxim without qualification", meaning "to a
(meaning "from") is often omitted when this phrase is used in
hoc ergo propter hoc, in which the chronological ordering of a correlation is insignificant.
●Contradictory Premises矛盾前提Conclusions are drawn from the interactions of premises: where two premises contradict each other, there can be no interaction and hence no conclusion. Similarly, if the definitions of two terms conflict with or exclude each other, then those two terms cannot be simultaneously ascribed to a single object or event.
●Ad Misericordiam文不对题is a fallacy in which someone tries to win support for an argument or idea by exploiting her or his opponent's feelings of pity or guilt. The appeal to pity is a specific kind of appeal to emotion.
●False Analogy错误类比is an informal fallacy applying to inductive arguments. It is often mistakenly considered to be a formal fallacy, but it is not, because a false analogy consists of an error in the substance of an argument (the content of the analogy itself), not an error in the logical structure of the argument.
●Hypothesis Contrary to Fact 与事实相反的假设This fallacy consists in treating a hypothetical claim as if it were a statement of fact by making a claim, without sufficient evidence, about what would have
happened in the past if other conditions had been present or an event that will occur in the future.
●Poisoning the Well井下放毒(or attempting to poison the well) is a logical fallacy where adverse information about a target is pre-emptively presented to an audience, with the intention of discrediting or ridiculing everything that the target person is about to say.。