Fact

A fact is a true datum about a circumstance or an occurrence in the real world. It describes a state of affairs that is the case. Generally, facts are considered independent of belief, knowledge, or opinion. This means a fact remains true regardless of what a person thinks about it. For example, the statement "the Sun is a star" is an astronomical fact. A linguistic fact might be the observation that a specific sentence contains words. Facts are distinct from other concepts like inferences, theories, values, or objects. While a theory tries to explain why things happen, a fact is the actual occurrence itself.

To understand how facts function, we can look at their internal structure. Many thinkers believe that non-trivial true statements about reality are abstractions. These are composed of a complex of objects, properties, or relations. For instance, the statement "Paris is the capital city of France" describes a complex fact. This fact implies the existence of Paris and France. It also implies the existence of capital cities and governments. It further implies that the French government has the power to define its capital. It also implies that the government has chosen Paris. All these individual assertions must coincide to create the single fact.

There are different ways to categorize how we use the word "fact." In a legal or common sense, it can mean something that has really occurred. However, it can also be used to indicate an allegation. In this context, a "fact" might be something that may or may not be true. For example, someone might say an author's facts are not trustworthy. Another usage refers to findings derived through a process of evaluation. This is seen in terms like "fact-finding commissions." These groups use direct observation or the review of testimony to reach conclusions. These findings are distinguished from mere speculation or inference.

History and language show how our understanding of facts has evolved. The word derives from the Latin term "factum." In the 16th century, it originally meant a thing done or performed. By the mid-16th century, the meaning shifted to something that actually occurred. In 1870, Charles Sanders Peirce described four methods for deciding what to believe. These methods included tenacity, the method of authority, a priori, and the scientific method. In the field of history, scholars like E. H. Carr have noted the difficulty of objectivity. Carr argued that the biases involved in gathering facts make a perfectly objective history impossible. He suggested that history is a conversation between the present and the past.

In science, the definition of a fact is more specific and implies knowledge. A scientific fact is the result of repeatable, careful observation or measurement. This is often called empirical evidence. These facts are central to building scientific theories. Scientists distinguish between states of affairs in the external world and assertions of fact used in analysis. Some scholars argue that facts are "theory-laden." This means that knowing what to measure requires using other theories. For example, determining the age of fossils requires the theory of radioactive decay. This shows that the tools we use to find facts are often shaped by our existing scientific knowledge.

Philosophers study facts through specific branches of study. Epistemology is the branch concerned with knowledge and truth. Ontology is the branch that studies existence, being, and reality. One famous idea is the correspondence theory of truth. This theory suggests that a sentence is true because it corresponds to a fact. This idea assumes that an objective world exists. Another concept is the "is–ought" distinction made by David Hume. He argued that you cannot derive a value from a fact. For example, the fact that people need food does not logically prove the value that it is "good" to give it. This creates a clear boundary between factual statements and moral values.

Finally, facts can be contrasted with other logical concepts. One such concept is counterfactuality. A counterfactual is a statement about what might have occurred but did not. An example is saying that if a leader had lived, their empire would have been larger. This is different from an indicative conditional, which describes what is actually the case. In mathematics, the concept is also specialized. A mathematical fact is often called a theorem. A theorem is a statement that can be proven through logical argument. It relies on specific definitions and axioms to reach a certain conclusion.