overgeneralize

Overgeneralize refers to the act of applying a rule beyond its appropriate scope. In linguistics and everyday reasoning, it describes extending patterns learned from limited data to cases where they do not apply. The result is a broader, incorrect generalization that can affect language, thought, and behavior.

In language, overgeneralization is common during child language development and can also appear in adult speech. A productive rule, such as adding -ed to verbs to form past tense, can be applied to irregular verbs, producing forms like goed for went, ranned for ran, or runned for ran. Similarly, regular plural endings may be added to irregular nouns, yielding mouses for mice or foots for feet. These errors typically reflect the learner’s attempt to systematize structure from patterns rather than memorize every irregular form, and they often diminish with feedback and further exposure.

Beyond language, overgeneralization describes a cognitive bias where people draw sweeping conclusions from limited observations. Early experiences or partial data can lead to beliefs like “all X are Y,” until counterexamples are encountered. Such generalizations can guide hypothesis formation and learning but may also produce enduring misconceptions if not corrected.

Causes and consequences vary by domain. In development, overgeneralization is a normal, often temporary phase signaling rule discovery and testing. In adults or machines, it may signal insufficient data coverage or model misspecification. Mitigation involves exposure to a broader range of examples, feedback that highlights exceptions, and, in machine learning, techniques that reduce reliance on overly simple rules.

See also: rule-based learning, hypothesis testing, language acquisition.