A proposition is a term in philosophy and logic. It is a statement which has a truth value, meaning it can be proved to be true or false. For a proposition to be valid, it must be possible to prove the proposition is either true or false. Many teachers and students of logic use the term "statement" and "proposition" to mean the same thing. Propositions are also often represented by capital letters such as formula_1, formula_2 and formula_3. 