hypothetical proposition

logic

Also known as: conditional proposition, conditional sentence

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 29, 2026

Quick Summary

A hypothetical proposition is a statement that presents a conditional idea, often in the form of an "if-then" statement. These propositions are fundamental in logic and serve as building blocks for more complex reasoning.12

A hypothetical syllogism is a type of logical argument that is composed entirely or partly of hypothetical propositions. This contrasts with categorical propositions, which are direct assertions or denials about a subject and predicate. Hypotheticals, in a broader sense, can be considered assumptions or premises used as a starting point for reasoning.314

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

5 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

categorical proposition
…connections, they contrast especially with hypothetical propositions, such as “If every man is mortal, then Socrates is mortal.”
Read More
…connections, they contrast especially with hypothetical propositions, such as “If every man is mortal, then Socrates is mortal.”
Read More

condition
… ⊃ B] is called a conditional (sentence or proposition). Similarly, “Whenever A then B” {in symbols, (x) [A(x) ⊃ B(x)]} may be called a general conditional. In such uses, “conditional” is a synonym for “hypothetical” and is opposed to “categorical.” Closely related in meaning are the common and useful expressions…
Read More
… ⊃ B] is called a conditional (sentence or proposition). Similarly, “Whenever A then B” {in symbols, (x) [A(x) ⊃ B(x)]} may be called a general conditional. In such uses, “conditional” is a synonym for “hypothetical” and is opposed to “categorical.” Closely related in meaning are the common and useful expressions…
Read More

history of logic
The Megarians and the Stoics
…also proposed an interpretation of conditional propositions. He held that the proposition “If p, then q” is true if and only if it neither is nor ever was possible for the antecedent p to be true and the consequent q to be false simultaneously. Given Diodorus’s notion of possibility, this…
Read More
…also proposed an interpretation of conditional propositions. He held that the proposition “If p, then q” is true if and only if it neither is nor ever was possible for the antecedent p to be true and the consequent q to be false simultaneously. Given Diodorus’s notion of possibility, this…
Read More

history of logic
Theophrastus of Eresus
A hypothetical proposition, for Theophrastus is a proposition made up of two or more component propositions (e.g., “p or q,” or “if p then q”), and a hypothetical syllogism is an inference containing at least one hypothetical proposition as a premise. The extent of Theophrastus’s work…
Read More
A hypothetical proposition, for Theophrastus is a proposition made up of two or more component propositions (e.g., “p or q,” or “if p then q”), and a hypothetical syllogism is an inference containing at least one hypothetical proposition as a premise. The extent of Theophrastus’s work…
Read More