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Converse Accident
Hasty Generalization

Diagram of Converse Accident Abstract:
Converse accident occurs when a generalization about all instances of a kind is based on too few examples, atypical examples, or examples of a different kind.

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I. Converse Accident: (hasty generalization) the fallacy of considering two few cases or certain exceptional cases and generalizing to a rule that fits them alone. (Note that the fallacy of converse accident is the opposite of the fallacy of accident.)

  1. Thus, in the fallacy of converse accident a generalization is made on the basis of insufficient evidence or on the basis of only a few examples.

    Consider these examples of converse accident:

    1. The following argument was offered in a popular magazine to encourage older persons to begin an exercise program:
      “It's never too late to get fit. When Mark Tarnopolsky, M.D., a professor of pediatrics at McMaster University in Hamilton, Ontario, took mice bred to age at an accelerated rate and had them start running as late teenagers, the course of their lives changed. Within five months (the equivalent of nearly 20 years in people), the nonrunning control mice were frail, gray, bald, and dying. But the runners still had virtually all of their youthful muscle mass, balance, mental acuity, and fur.”

      [Gretchen Reynolds, “Stay Healthy,” Parade (April 29, 2012), 18.]
      Analysis: From the example of an experiment with in-bred “teenage” mice whose life was extended by running, the author of this article concludes atypically that all persons including older persons can get fit. Here are some of the difficulties with this argument:

      “Spontaneous Activity Wheel,” photograph; Bioseb 
		Research Instruments US & Canada
      Third, the control mice were dying at a proportional age of under 40 in “human-year parity,” whereas human beings do not commonly die at this age; fourth, the results of one experiment with young mice is being generalized to apply to older human beings. Control mice at the corresponding “human age” of 40 were frail, gray, bald, and dying, whereas human beings who do not exercise are not frail, gray, bald, and dying at that age.

      Fifth, running by mice is not the same kind of exercise as running done by human beings: mice run on four limbs and human beings run on two.

      Other differences can be drawn from the genetic variability of human beings to the environmental and dietary dissimilarities between mice and human beings.

    2. E.g., The following argument is raised to oppose the view that boys have greater inherent mathematical ability:
      “When I was four, my father taught me the beauty of numbers, and I have excelled in mathematics ever since. My conclusion? The males who grew up with a high aptitude for math are not spending enough time with their daughters.”

      [Nancy Whelan Reese, “Letters,” Time 117, No. 1 (January 4, 1981), 6.]
      Analysis: From the one example of herself doing well in mathematics, this writer concludes a generalization about what all women who have teaching fathers with high mathematical aptitudes could achieve.

    3. Converse accident fallacies arise since many different logical generalizations are consistent with a finite amount of data. But not all of those generalizations are consistent with each other.

  2. The concluding generalization of this fallacy is sometimes made on the basis of carelessly selected evidence. Consider the following examples.

    1. E.g., “I interviewed ten people on Main Street in Greenwood on Friday night, and they all stated they would rather be there than watching TV. I conclude that the folks in Greenwood don't like to watch TV on Friday night.”

    2. E.g., “As I drove to school this morning, not one car which was turning had its turn signal on. Thus, I conclude that drivers in this city are not trained to drive very well.”

    3. E.g., “The induction problem forever haunts us. How many instances of a class must be observed before one can be really sure? Having experienced two uncoordinated woman-drivers, am I justified in making a generalization about woman-drivers? (For too many men, a sampling of two seems to justify such a generalization. Women, of course, never make this sort of error.)”

      [James L. Christian, Philosophy: An Introduction to the Art of Wondering (New York: Holt, Rinehart and Winston 1990), 181]

      Note, as well, Christian's generalization about women.

    4. “As legislators, women make a difference. They are far more likely to identify problems of gender bias, and we know this firsthand. Cokie's mom, Lindy Goggs, served 18 years in Congress and authored legislation banning discrimination against women in bank lending practices.”

      [Cokie Roberts and Steve Roberts, “Women Are Flexing Their Political Muscles,” Index-Journal 94 No. 153 (September 30, 2012), 11A. Emphasis added.]

  3. Converse accident in some passages is sometimes difficult to identify; in such cases, it is often helpful to reconstruct the argument from its context:
    “[T]he president [commented] last February: ‘One of the proudest things in my three years in office is helping to restore a sense of respect for America around the world.’ In light of the uprising that included the burning of American flags in the Middle East and the murder of Americans in Libya, that's one more broken promise that can be added to a growing list.”

    [Cal Thomas, “Distractions and Diversions,”; Index-Journal 94 Vol. 146 (September 24, 2012), 8A.]
    Adapted from “Timeline: Anti-US Protests,” 
	photograph, Voice of America: September 11, 2012 In this example, the generalization that there is a growing respect for America around the world is opposed by the statements of two tragic events. The two tragic events are cited in support of an implicit generalization that the President is not helping to restore a sense of respect for America around the world.

    Since these two examples were not particularly atypical examples of events occurring in world then, this converse accident is fallacious even though the two examples constitute an extremely weak inductive argument lending “some” small degree of probability to the unstated implicit or enthymematic conclusion that the president is not helping to restore a sense of respect.

  4. Distinguishing Converse Accident from False Cause: Fallacies of converse accident and false cause generalizations are often difficult to distinguish from each other. (On occasion, both fallacies can be said to occur in the same fallacious argument.)

    1. Converse accident occurs when a generalization about all instances of a kind is based on either too few examples which are not known to be typical or based on instances of a different kind, whereas false cause occurs usually when the conclusion of a causal relation is based evidentially on a correlation in time or circumstance. The generalization in converse accident need not be causal, and the causal relation in false cause need not be general.

      Consider this example:
      “There's nothing you can't get used to. Just think about all the unpleasant things you've accepted as ordinary, like wading through traffic or dealing with a bad-tempered relative or coworker.”

      [Yongey Mingyur Rinpoche, The Joy of Living (New York: Harmony Books, 2007), 44.]
      The argument is that since you have gotten used to a few ordinary annoying situations, the conclusion then follows that you can get used to anything. No doubt the author would agree that one wouldn't adapt to waterboarding; so the argument is a hasty generalization. Also the author is not claiming that getting used to unpleasant things will cause an individual to become accustomed to anything. Since the conclusion is not a causal generalization, the argument is converse accident rather than false cause.

      Now consider this example:
      “[T]he market as a rule does better under Democratic presidents than their counterparts. Certainly, the last four years proves the point.”

      [Robert E. Anderson, “Mailbag: Earnings and Interest,” Barron's 92 No. 46 (November 12, 2012) , 50.]
      The last four years refers to the first Barack Obama administration when the stock market rose about 20% and this correlation is only one instance of a Democratic President and an improving market. The general conclusion is said to follow from this one correlation that the stock market does better under Democratic leadership than it does under Republican leadership.

      Since no causal relation is explicitly being asserted in the argument, the better identification of this fallacy is converse accident. Nevertheless, it is certainly arguable that the author implicitly intends a causal connection of some sort in the argument. But he is mistakenly taking this one instance (of the last four years) as a proof for a rule, rather than viewing past states of affairs as causal events.

    2. When the conclusion about a causal generalization is reached from a premise or from premises involving one or more atypical correlations or atypical causal relations either fallacy may be said to occur:
      “A balanced, healthy diet is the best remedy for disease in general. I have a cousin who is a breast cancer survivor, and she now consumes juiced fruits and vegetables in enormous quantities to keep herself healthy, and so far her cancer has stayed in complete remission.”

      Karen Lee, “Restoring Your Inner Balance — How to Stop the Aging Process in Its Tracks,” Pick the Brain, (accessed April 8, 2012).]
      The conclusion that the remedy for all diseases is affected by a good diet is based on the reason cited of a cousin whose healthy diet has kept her cancer in remission. This example can be identified as either converse accident or false cause since a causal relation of remedying all diseases is concluded from the correlation or causal relation of one person remedying one disease.

II. As a quick check of your understanding of converse accident, evaluate the following passages.
  1. “Joe Black, Brooklyn Dodgers,” Topps card, 
	SABR, Cronkite School at ASU “Former Brooklyn Dodger Joe Black, speaking in Clinton, helped put the drug situation in professional athletics in better perspective. The former pitcher, a black man, said he has no sympathy for the argument that pressures of the professional athlete's lifestyle can lead to drug abuse. ‘There are no pressures in professional sports that make you use drugs or booze. Jackie Robinson didn't use drugs. Willie Mays didn't use drugs. I didn't use drugs. That's a cop out,’ Black said.”

    [Index-Journal 64 No. 99 (August 8, 1982), B-3.]

  2. ”All persons admitted to Lander University must abide by its policies. Therefore you must abide by the university parking rules.”

  3. “The USDA policies for farmers are riddled with loopholes. Why I know a guy who collects thousands of dollars in farm subsidies for not planting any wheat and spends his spare time at the race track.

  4. “I'm generalizing from one example, here, but everyone generalizes from one example. At least, I do.”

    [Steven Brust, Issola (New York: Macmillan, 2002), Ch. 14.]

  5. “The external world is simply the suggestion, the occasion, which sets you to study your own mind, but the object of your study is always your own mind. The falling of an apple gave the suggestion to Newton, and he studied his own mind; he rearranged all the previous links of thought in his mind and discovered a new link among them, which we call the law of gravitation. It was not in the apple nor in anything in the centre of the earth. All knowledge therefore, secular or spiritual, is in the human mind.”

    [Swami Vivekananda, The Complete Works of the Swami Vivekananda (Mayavati: Advaita Ashram, 1915), 46.]

FIG. 2. Historical Frequency of Use of “Hasty Generalization,” secundum quid, Converse Accident in Google Books 1800-2019.

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