Faulty generalization

A faulty generalization is a conclusion about all or many instances of a phenomenon that has been reached on the basis of just one or just a few instances of that phenomenon. It is an example of jumping to conclusions. For example, we may generalize about all people, or all members of a group, based on what we know about just one or just a few people. If we meet an angry person from a given country X, we may suspect that most people in country X are often angry. If we meet a lazy recipient of social welfare benefits, we may suspect that all welfare recipients are lazy. Faulty generalizations may lead to further incorrect conclusions. We may for example conclude that citizens of country X are genetically inferior, or that poverty is generally the fault of the poor.

Expressed in more precise philosophical language, a fallacy of defective induction is a conclusion that has been made on the basis of weak premises. Unlike fallacies of relevance, in fallacies of defective induction, the premises are related to the conclusions yet only weakly buttress the conclusions. A faulty generalization is thus produced. This inductive fallacy is any of several errors of inductive inference.

Such a generalization proceeds from a premise about a sample to a conclusion about the population.

Faulty generalization is a mode of thinking that takes knowledge from one group's or person's experiences and incorrectly extends it to another.

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