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  • General

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  • 结构误差

    Consider the following statement:
    ::审议以下声明:

    “A black cat ran across the road on my way to school last Thursday and I had a horrible day, therefore black cats are bad luck”.
    ::“上星期四,一只黑猫在我上学的路上跑过路面,我度过了可怕的一天,因此黑猫是坏运气”。

    lesson content

    What is wrong with this argument? A black cat did cross my path, and I did have a bad day afterward, so both premises are true, but the conclusion is suspect. What went wrong with the argument?
    ::这个论点有什么错? 一只黑猫越过了我的道路, 之后我确实过了一个糟糕的一天, 所以两个前提都是真实的, 但结论是可疑的。这个论点有什么问题?

    See the end of the lesson for the answer.
    ::答案见课的结尾。

    Structural Fallacies
    ::结构误差

    Logical arguments are practically everywhere you look. Humans, almost by definition, are self-aware creatures with the ability to reason and the desire to share their reasoning with others. Because of this tendency, it is very valuable to be more than a little bit familiar with the rules of valid argument, and the types of logical fallacies that make arguments invalid.
    ::逻辑论理几乎随处可见。 人类几乎从定义上讲,是自觉的生物,有能力理性,愿意与他人分享其推理。 由于这一趋势,非常有价值的是更熟悉有效论理的规则,以及使论理无效的逻辑谬误类型。

    In this lesson, we will practice identifying some common formal fallacies . It is important to note that identifying an argument as invalid because it follows the form of a common fallacy may require that you first reconstruct the argument in a standard form, since arguments often rely on unstated hidden premises (see the first example).
    ::在这个教训中,我们将在实践中找出一些共同的正式谬误,必须指出,如果将一个论点确定为无效,因为它遵循的是共同谬误的形式,这可能需要你首先以标准的形式重新表述这一论点,因为论据往往依赖未经说明的隐蔽前提(见第一个例子)。

    Common Fallacies:
    ::共同误判:

    • Affirming the Consequent : If A then B. B, therefore A.
      • If it is snowing, I wear my boots.  I am wearing my boots, therefore it is snowing.
        ::如果下雪,我穿靴子,我穿靴子,所以下雪。
      • Just because I wear my boots when it is snowing does not mean I don’t also wear my boots for some other reason.
        ::也并非因为其他原因不穿靴子。

      ::声明:如果当时是A,那么B.B,那么A。如果下雪,我穿我的靴子,我穿我的靴子,我穿我的靴子,所以是雪。 下雪时我穿我的靴子,并不代表我不穿我的靴子是为了其他原因。
    • Appeal to Ignorance : Use the absence of proof for a premise as evidence in favor of the opposing premise.
      • There are no fossilized remains of a winged snake, so snakes must not have evolved into birds.
        ::蛇翼蛇的残骸没有化石 所以蛇一定没有进化成鸟
      • The lack of proof of winged snakes is not, in and of itself, proof either for or against the evolution of snakes to birds.
        ::缺乏有翅膀的蛇的证据本身并不能证明蛇向鸟类的进化。

      ::无知的吸引力:用缺乏证据的前提作为支持相反前提的证据。 翼蛇的残骸没有化石化,因此蛇一定不会演变成鸟类。 翼蛇缺乏证据本身并不能证明蛇对鸟类的进化。
    • Diversion : Trying to support one premise by arguing for other premise.
      • ABC Dog Food is flavored with beef-like flavoring.  According to studies, dogs choose hamburgers 3:2 over chicken tenders, so ABC Dog Food is the best.
        ::ABC Dog Food有类似牛肉的口味。 根据研究,狗选择汉堡3: 2而不是鸡标,所以ABC Dog Food是最好的。
      • Showing that dogs prefer hamburger to chicken tenders is not evidence that ABC Dog Food tastes better than any other dog food.
        ::说明狗更喜欢汉堡而不是鸡标, 并不能证明ABC狗食品比其他狗食品好吃。

      ::转基因:试图通过为其他前提辩护来支持一个前提。 ABC Dog Food有类似牛肉的口味。 根据研究,狗选择汉堡3:2而不是鸡标价,因此ABC Dog Food是最好的。 显示狗更喜欢汉堡而不是鸡标价并不能证明ABC Dog Food比其他狗食品好吃。
    • Equivocation : Using one meaning of a word in the premise, and another in the conclusion.
      • Criminal actions are illegal.  All murder trials are criminal actions.  Therefore all murder trials must be illegal.
        ::所有谋杀审判都是犯罪行为,因此所有谋杀审判都必须是非法的。

      ::免责:在前提中使用一个词的含义,在结论中使用另一个含义;犯罪行为是非法的;所有谋杀审判都是犯罪行为;因此,所有谋杀审判都必须是非法的。
    • Coincidental Correlation (also known as “post hoc ergo propter hoc”, which means “after this, therefore because of this” or just “post hoc”):  Falsely assuming that just because one thing occurs after another, it must have been  caused by the other.
      • Public school attendance has skyrocketed in the past 10 years, and so has the number of kids in juvenile hall, so school must be corrupting children.
        ::过去十年来,公立学校的出勤率飞涨,青少年宿舍中的儿童人数也急剧上升,因此学校必须腐蚀儿童。

      ::偶然关系(又称“后临时生化实验 ” ) , 意思是“在此之后,由于这个原因 ” , 或者只是“后临时生 ” : 错误地假设,仅仅因为一件事情发生在另一件事情之后,它一定是另一件事情造成的。 在过去10年中,公立学校的出勤率猛增,青少年宿舍里的儿童人数也激增了,所以学校一定在腐蚀儿童。

    Identifying Logical Fallacies 
    ::查明逻辑误判

    1. Identify the logical fallacy in the argument below:
    ::1. 确定以下论点中的逻辑谬误:

    The once-blind man could obviously see, since he picked up his hammer and saw.
    ::曾经盲目的人看得很清楚,因为他拿起锤子和锯子。

    This is an example of equivocation , since the premise uses the word “see” to describe the ability to perceive an object with one’s eyes, while the conclusion uses the word “saw”, meaning the cutting implement rather than the past tense of the word in the premise.
    ::这是一个模棱两可的例子,因为这一前提使用 " 见 " 一词来描述用人的眼睛看待物体的能力,而结论则使用 " 锯 " 一词,意思是削减执行而不是在前提中用过去时态来表示。

    2. Identify the logical fallacy:
    ::2. 查明逻辑谬误:

    My dad to refused to pay methe allowance I earn by doing my chores, even after I proved that gas prices have gone up by $0.25 per gallon. He just kept pointing out that my chores weren’t done. I think he should pay me extra so I can afford gas.
    ::我父亲拒绝支付我通过做家务而得到的津贴,即使我证明煤气价格每加仑上涨0.25美元。 他只是不停地指出我的杂务没有完成。 我认为他应该多付我一些钱,这样我才能买得起煤气。

    This is an example of a diversion . The allowance is based on the completion of chores, so any evidence of an unrelated premise such as gas pricing is not going to strengthen the argument that allowance should be paid.
    ::这是一个转移用途的例子,津贴的依据是家务的完成,因此任何关于诸如天然气定价等无关的前提的证据都不会加强应支付津贴的论点。

    The fallacy is clear if the argument is stated in a standard form:
    ::如果论点以标准形式表述,则谬误是显而易见的:

    Premise 1: Dad refuses to pay allowance
    ::预言1:爸爸拒绝支付津贴

    Premise 2: Allowance is based on chores
    ::预测2:津贴以家务劳动为基础

    Premise 3: Gas prices have increased
    ::预测3:天然气价格上涨

    Conclusion: Allowance should be paid, and increased
    ::结论:应支付并增加津贴

    Stated this way, it seems pretty clear that the conclusion is based only on the unrelated premise that gas prices have increased, rather than on the valid premises that allowance is linked to chores and that chores weren’t done.
    ::以这种方式指出,似乎相当清楚的是,这一结论所根据的只是天然气价格上涨这一无关的前提,而不是有效的前提,即津贴与家务有关,家务没有做。

    3. Identify the logical fallacy:
    ::3. 查明逻辑谬误:

    Scientists have been trying for years to prove that ghosts do not exist. Since there is no proof yet that they don’t exist, they must be real.
    ::科学家们多年来一直试图证明鬼魂并不存在。 因为还没有证据表明鬼魂不存在,所以它们必须是真实的。

    This is an Appeal to Ignorance . The premise is that the lack of proof against ghosts may be taken as proof for the existence ghosts.
    ::这是对无知的吸引力,其前提是,对幽灵缺乏证据可被视为存在幽灵的证据。

    Earlier Problem Revisited
    ::重审先前的问题

    “A black cat ran across the road on my way to school last Thursday and I had a horrible day, therefore black cats are bad luck”.
    ::“上星期四,一只黑猫在我上学的路上跑过路面,我度过了可怕的一天,因此黑猫是坏运气”。

    What is wrong with this argument? A black cat did cross my path, and I did have a bad day afterward, so both premises are true, but the conclusion is suspect. What went wrong with the argument?
    ::这个论点有什么错? 一只黑猫越过了我的道路, 之后我确实过了一个糟糕的一天, 所以两个前提都是真实的, 但结论是可疑的。这个论点有什么问题?

    This is an example of “post hoc”, meaning that the conclusion is based on the false assumption that the bad day that occurred after the black cat crossed the path was caused by the black cat.
    ::这是“事后临时”的一个例子,即结论是基于一种虚假的假设,即黑猫跨过这条路之后发生的坏日子是由黑猫造成的。

    Examples 
    ::实例

    Consider the following statements:
    ::审议以下声明:

    Damien said he would ask Carrie to the dance if he won the lottery. Damien is at the dance with Carrie, so he must have won the lottery.
    ::达米安说,如果卡莉赢了彩票,他会邀请卡莉参加舞会。 达米安在和卡莉跳舞,所以他一定是中了彩票。

    Example 1
    ::例1

    What are the premises to the argument?
    ::争论的前提是什么?

    Premise 1: Damien said he would ask Carrie to the dance if he won the lottery Premise 2: Damien is at the dance with Carrie.
    ::达米安说,如果卡莉赢了彩票2: 达米安在和卡莉跳舞,他会邀请卡莉参加舞会。

    Example 2
    ::例2

    What is the conclusion?
    ::结论是什么?

    Conclusion: Damien won the lottery.
    ::结论:达米安中了彩票。

    Example 3
    ::例3

    Is the argument valid?
    ::论点是否有效?

    The argument is invalid. We can tell because it fits the form of a common formal fallacy.
    ::这个论点是无效的,我们可以分辨,因为它符合形式上通常的谬误。

    Example 4
    ::例4

    What fallacy, if any, is demonstrated?
    ::如果有任何谬误,说明什么是谬误?

    The conclusion is based on the logic: If A, then B. B, so A. This is the fallacy known as affirming the consequent .
    ::结论基于逻辑:如果是A,那么B.B.,那么A.,这就是所谓确证结果的谬误。

    Review 
    ::回顾

    Questions 1-4 refer to the following argument:
    ::问题1-4提到以下论点:

    If it is sunny outside, I wear sandals. I am wearing sandals, so it must be sunny outside.
    ::如果外面阳光明媚,我穿凉鞋,我穿凉鞋,所以外面一定阳光明媚。

    1. What are the premises in the argument?
    ::1. 争论的前提是什么?

    2. What is the conclusion?
    ::2. 结论是什么?

    3. Is the argument valid?
    ::3. 论点是否有效?

    4. What fallacy, if any, is demonstrated?
    ::4. 如果有任何谬误,说明什么是谬误?

    Questions 5-8 refer to the following:
    ::问题5-8涉及以下方面:

    You can’t prove I threw the water balloon, so my sister must have done it.
    ::你无法证明我扔了水气球,

    5. What are the premises in the argument?
    ::5. 争论的前提是什么?

    6. What is the conclusion?
    ::6. 结论是什么?

    7. Is the argument valid?
    ::7. 论点是否有效?

    8. What fallacy, if any, is demonstrated?
    ::8. 如果有任何谬误,说明什么是谬误?

    Questions 9-12 refer to the following:
    ::问题9-12涉及以下方面:

    I teach math and science classes. Physics is a science class and everyone thinks it is the coolest subject in science. Therefore I am the best teacher in school.
    ::我教数学和科学课,物理是科学课,每个人都认为这是科学中最酷的科目。因此我是学校最好的教师。

    9. What are the premises in the argument?
    ::9. 争论的前提是什么?

    10. What is the conclusion?
    ::10. 结论是什么?

    11. Is the argument valid?
    ::11. 论点是否有效?

    12. What fallacy, if any, is demonstrated?
    ::12. 如果有任何谬误,说明什么是谬误?

    Questions 13-16 refer to the following:
    ::问题13-16涉及以下方面:

    My mom always told me not to talk to strangers. You are as strange as anyone I know, so mom wouldn’t want me to speak with you.
    ::我妈妈总是告诉我不要和陌生人说话。 你跟我认识的人一样奇怪,所以妈妈不想让我跟你说话。

    13. What are the premises in the argument?
    ::13. 争论的前提是什么?

    14. What is the conclusion?
    ::14. 结论是什么?

    15. Is the argument valid?
    ::15. 这一论点是否有效?

    16. What fallacy, if any, is demonstrated?
    ::16. 如果有任何谬误,说明什么是谬误?

    Review (Answers)
    ::回顾(答复)

    Click to see the answer key or go to the Table of Contents and click on the Answer Key under the 'Other Versions' option.
    ::单击可查看答题键, 或转到目录中, 单击“ 其他版本” 选项下的答题键 。