Overview
A fact is a true datum about one or more aspects of a circumstance. Standard reference works are often used to check facts. Scientific facts are verified by repeatable careful observation or measurement by experiments or other means.
For example, "This sentence contains words." accurately describes a linguistic fact, and "The sun is a star" accurately describes an astronomical fact. Further, "Abraham Lincoln was the 16th President of the United States" and "Abraham Lincoln was assassinated" both accurately describe historical facts. Generally speaking, facts are independent of belief and of knowledge and opinion.
Facts are different from inferences, theories, values, and objects.
Etymology and usage
The word fact derives from the Latin factum. It was first used in English with the same meaning: "a thing done or performed"a meaning now obsolete. The common usage of "something that has really occurred or is the case" dates from the mid-16th century.
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