Hasty Generalization (Fallacy)

Logical Fallacies: Examples of Hasty Generalizations

Batman and Robin
Adam West and Bruce Ward as Batman and Robin in the U.S. television series Batman (1966). See the Lighter Side of Hasty Generalizations, below. Silver Screen Collection/Getty Images


A hasty generalization is a fallacy in which a conclusion is not logically justified by sufficient or unbiased evidence. Also called insufficient sample, converse accident, faulty generalization, biased generalization, jumping to a conclusion, secundum quid, and neglect of qualifications.

By definition, an argument based on a hasty generalization always proceeds from the particular to the general.

See Examples and Observations below. Also see:


Examples and Observations

  • "A hasty generalization is a broad claim based on too-limited evidence. It is unethical to assert a broad claim when you have only anecdotal or isolated evidence or instances. Consider two examples of hasty generalizations based on inadequate data:
    - Three congressional representatives have had affairs. Therefore, members of Congree are adulterers.

    - An environmental group illegally blocked loggers and workers at a nuclear plant. Therefore, environmentalists are radicals who take the law into their own hands.
    In each case, the conclusion is based on limited evidence. In each case the conclusion is hasty and fallacious."
    (Julia T. Wood, Communication in Our Lives, 6th ed. Wadsworth, 2012)
  • "It was a rainy day in Harvard Square, so the foot traffic through the atrium from Mass Ave to Mount Auburn Street was heavier than it might have been if the sun were out. A lot of people were carrying umbrellas, which most of them furled inside. I had always thought that Cambridge, in the vicinity of Harvard, might have had the most umbrellas per capita of any place in the world. People used them when it snowed. In my childhood, in Laramie, Wyoming, we used to think people who carried umbrellas were sissies. It was almost certainly a hasty generalization, but I had never encountered a hard argument against it."
    (Robert B. Parker, Sixkill. Putnam, 2011)
  • "It is not uncommon for an arguer to draw a conclusion or generalization based on only a few instances of a phenomenon. In fact, a generalization is often drawn from a single piece of supporting data, an act that might be described as committing the fallacy of the lonely fact. . . .

    "Some areas of inquiry have quite sophisticated guidelines for determining the sufficiency of a sample, such as in voter preference samples or television viewing samples. In many areas, however, there are no such guidelines to assist us in determining what would be sufficient grounds for the truth of a particular conclusion."
    (T. Edward Damer, Attacking Faulty Reasoning, 4th ed. Wadsworth, 2001)
  • "A United States Judge indulged in a very hasty generalization when in the recent trial of an alimony case he interjected the remark that 'any man who gives all his salary to his wife is a fool.' Many men not fools, but wise and prudent, turn over their earnings to their wives as the most competent stewards of the household."
    ("The Wife As the Family Treasurer," The Toronto Truth. July 29, 1895)
  • The Lighter Side of Hasty Generalizatios
    - Robin: I guess you can never trust a woman.
    Batman: You've made a hasty generalization, Robin. It's a bad habit to get into.
    (Batman television series, 1966)

    - "Next we take up a fallacy called Hasty Generalization. Listen carefully: You can't speak French. I can't speak French. Petey Burch can't speak French. I must therefore conclude that nobody at the University of Minnesota can speak French."

    "Really," said Polly, amazed. "Nobody?"

    I hid my exasperation. "Polly, it's a fallacy. The generalization is reached too hastily. There are too few instances to support such a conclusion."
    (Max Shulman, The Many Loves of Dobie Gillis. Doubleday, 1951)