第5章論理学と推論Logic and Reasoning

Red Herring燻製ニシンによる論点そらし

A red herring fallacy is like a strawman, except the arguer completely ignores their opponent’s position and simply changes the subject. The arguer diverts the attention of the audience to a new subject. A red herring is a smelly smoked fish that was used to train hunting dogs to track smells by dragging this fish along a path as practice. So the fallacy gets its name because it means to trick people into following a different path of reasoning than the one at hand. You may wonder how a person can get away with simply changing the subject. Successful use of the red herring usually involves shifting the subject to something tangentially related. Here is an example:

英語のヒント

燻製ニシンの誤謬は、藁人形の誤謬に似ているが、論証する人が、相手の立場をまったく無視して、単に話題を変える点が異なる。聴衆の注意を、新しい話題へそらすのだ。red herringは、においの強い燻製の魚である。猟犬がにおいを追う訓練で、道に沿ってこの魚を引きずって使われた。そのため、この誤謬には、人をだまして、目の前の推論とは違う道筋を追わせるという意味で、この名がついている。話題を変えるだけで、どうして通用するのかと思うかもしれない。うまくいく論点そらしでは、通常、少しだけ関係のあることへ話題を移す。例を示す。

My daughter wants me to exercise more. She said she is worried about my health. She showed me research about cardiovascular fitness and its impact on quality of life for people my age and older. She suggested I start biking with her. But bicycles are expensive. And it is dangerous to ride bicycles on a busy road. Furthermore, I do not have a place to store a bicycle.
娘は私にもっと運動してほしがっている。私の健康が心配だと言い、心肺機能と、それが私の年代以上の人の生活の質に与える影響についての研究を見せた。一緒に自転車に乗り始めようと提案してきた。しかし、自転車は高い。交通量の多い道路で乗るのは危険だ。そのうえ、自転車を置く場所もない。

This arguer first summarizes the daughter’s position that they ought to exercise more. But then they take the suggestion of bicycling and veer off topic (getting more exercise) to the feasibility of cycling instead. The comments on bicycling in no way address the daughter’s general conclusion that the arguer needs to exercise more. Because the argument changes the subject, it is a red herring.

英語のヒント

この人はまず、自分がもっと運動するべきだという娘の立場を要約している。しかし、その後は自転車の提案だけを取り上げ、もっと運動するという話題から、自転車に乗ることの実行可能性へと話をそらしている。自転車についての発言は、この人がもっと運動する必要があるという娘の一般的な結論に、まったく答えていない。論証が話題を変えているので、これは燻製ニシンの誤謬である。

Table 5.3 summaries these many types of informal fallacies.

表5.3は、非形式的誤謬の多くの種類をまとめたものだ。

**Table 5.3** Types of Informal Fallacies
**表5.3**　非形式的誤謬の種類
General Category 一般的な分類	Specific Type 個別の種類	Description 説明
Fallacies of relevance—rely on evidence that is not relevant for logically establishing a conclusion 関連性の誤謬――結論を論理的に確立することと無関係な証拠に頼る。
	Appeal to emotion 感情への訴え	Appeals to feelings (whether positive or negative) rather than discussing the merits of an idea or proposal 考えや提案のよしあしを論じる代わりに、肯定的または否定的な感情に訴える。
	Ad hominem attack 人身攻撃	Argues against someone’s idea or suggestion by attacking the individual personally, rather than pointing out problems with the idea or suggestion 考えや提案の問題点を指摘する代わりに、提案した本人を個人的に攻撃して、その考えや提案に反論する。
Fallacies of weak induction—rely on evidence or reasons that are too weak to firmly establish a conclusion 弱い帰納の誤謬――結論を確立するには弱すぎる証拠や理由に頼る。
	Hasty generalization 性急な一般化	Draws a conclusion using too little evidence to support the conclusion 結論を支持するには少なすぎる証拠を使って、結論を導く。
	Biased sample 偏った標本	Draws a conclusion using evidence that is biased in some way 何らかの仕方で偏った証拠を使って、結論を導く。
	Appeal to ignorance 無知への訴え	Relies on the lack of knowledge or evidence for a thing (our ignorance of it) to draw a definite conclusion about that thing ある物事の知識や証拠の欠如、すなわちそれについての無知に頼って、その物事について確定的な結論を導く。
	False cause attribution 誤った原因の帰属	A causal relation is assumed to exist between two events or things that are not causally connected; “correlation does not equal causation” 因果的に結びついていない二つの出来事や物事のあいだに、因果関係があると想定する。「相関は因果と同じではない」。
Fallacies of unwarranted assumption—rely on information or beliefs that require further justification 不当な想定の誤謬――さらに正当化を必要とする情報や信念に頼る。
	False dichotomy 偽の二分法	A limited number of possibilities are assumed to be the only available options 限られた数の可能性だけが、取りうる選択肢のすべてだと想定する。
	Begging the question 論点先取	Either assumes the truth of a conclusion in the course of trying to prove it or assumes the truth of a contentious claim 結論を証明しようとする過程で、その結論の真を仮定するか、争いのある主張の真を仮定する。
Fallacies of diversion—rely on attempts to distract the attention of the audience away from the argument at hand 論点をそらす誤謬――聴衆の注意を、目の前の論証からそらそうとする。
	Strawman 藁人形	Utilizes a weaker version of the position being argued against in order to make the position easier to defeat 相手の立場を容易に打ち負かすために、弱めた形の立場を使う。
	Red Herring 燻製ニシンによる論点そらし	Ignores the opponent’s position and simply changes the subject 相手の立場を無視し、単に話題を変える。

Summaryまとめ

A fallacy is a poor form of reasoning. Fallacies that cannot be reduced to the structure of an argument are called informal fallacies. There are many types of informal fallacies, which can be sorted into four general categories according to how the reasoning fails. These categories are fallacies of relevance, fallacies of weak induction, fallacies of unwarranted assumption, and fallacies of diversion. A fallacy of relevance occurs when the arguer presents evidence that is not relevant for logically establishing their conclusion. The fallacies of weak induction occur when the evidence used is relevant but is too weak to support the desired conclusion. The fallacies of unwarranted assumption occur when an argument assumes, as evidence, some reason that requires further justification. The fallacies of diversion occur when the arguer attempts to distract the attention of the audience from the argument at hand.

誤謬とは、不適切な推論の形式である。論証の構造だけには還元できない誤謬を、非形式的誤謬と呼ぶ。多くの種類があるが、推論の失敗の仕方によって、関連性の誤謬、弱い帰納の誤謬、不当な想定の誤謬、論点をそらす誤謬という、四つの一般的な分類に分けられる。関連性の誤謬は、結論を論理的に確立することと無関係な証拠を提示するときに生じる。弱い帰納の誤謬は、証拠に関連性はあるが、目指す結論を支持するには弱すぎる場合に生じる。不当な想定の誤謬は、さらに正当化が必要な理由を、証拠として仮定するときに生じる。論点をそらす誤謬は、聴衆の注意を、目の前の論証からそらそうとするときに生じる。

Review Questions復習問題

What are the four general categories of informal fallacies?

非形式的誤謬の四つの一般的な分類は何か。

What is the difference between fallacies of relevance and fallacies of weak induction?

関連性の誤謬と、弱い帰納の誤謬の違いは何か。

What is problematic with appealing to emotion in an argument, and how does this qualify it as a fallacy of relevance?

論証で感情に訴えることには、どんな問題があるか。また、それはどのような点で、関連性の誤謬に当たるのだろうか。

Explain what a fallacy of unwarranted assumption is, and offer an example of one.

不当な想定の誤謬とは何かを説明し、その例を一つ示してほしい。

References参考文献

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Aristotle. On Interpretation. Translated by Jean T. Oesterle. Milwaukee: Marquette University Press, 1962. https://www.google.com/books/edition/On_Interpretation/vXbkAAAAMAAJ?hl=en&gbpv=1

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Ad hominin attack

人身攻撃

fallacy of relevance that argues against someone’s idea or suggestion by attacking the individual personally, rather than pointing out problems with the idea or suggestion.

考えや提案の問題点を指摘する代わりに、本人を個人的に攻撃してその考えや提案に反論する、関連性の誤謬。

Appeal to ignorance

無知への訴え

a fallacy of weak induction that relies on the lack of knowledge or evidence for a thing (our ignorance of it) to draw a definite conclusion about that thing.

ある事柄についての知識や証拠の欠如、つまり無知に頼って、その事柄について確定的な結論を導く、弱い帰納の誤謬。

Begging the question

論点先取

a fallacy of unwarranted assumption that either assumes the truth of a conclusion in the course of trying to prove it or assumes the truth of a contentious claim.

結論を証明する過程で、その結論の真を仮定するか、争いのある主張の真を仮定する、不当な想定の誤謬。

Biased sample

偏った標本

a fallacy of weak induction that draws a conclusion using evidence that is biased in some way.

何らかの仕方で偏った証拠を使って結論を導く、弱い帰納の誤謬。

Emotional appeal

感情への訴え

fallacy of relevance that appeals to feelings (whether positive or negative) rather than discussing the merits of an idea or proposal.

考えや提案のよしあしを論じる代わりに、肯定的または否定的な感情に訴える、関連性の誤謬。

Fallacy

誤謬

a poor form of reasoning.

不適切な推論の形式。

Fallacy of diversion

論点をそらす誤謬

a general category of informal fallacies in which an arguer presents evidence that functions to divert the attention of the audience from the current subject of argument.

現在の論証の主題から聴衆の注意をそらすように働く証拠を示す、非形式的誤謬の一般的な分類。

Fallacy of relevance

第5章論理学と推論Logic and Reasoning

Red Herring燻製ニシンによる論点そらし

Summaryまとめ

Review Questions復習問題

Suggested Readings読書案内

References参考文献