Editing Propositional calculus (section)

=== Declarative sentences ===
Propositional logic deals with '''statements''', which are defined as declarative sentences having truth value.<ref name="ms8"/><ref name=":1" /> Examples of statements might include:

* ''[[Wikipedia]] is a free online encyclopedia that anyone can edit.''
* ''[[London]] is the capital of [[England]].''
* ''All [[Wikipedia community|Wikipedia editors]] speak at least three [[language]]s.''
Declarative sentences are contrasted with [[question]]s, such as "What is Wikipedia?", and [[Imperative mood|imperative]] statements, such as "Please add [[citation]]s to support the claims in this article.".<ref name="ms9"/><ref name="ms10"/> Such non-declarative sentences have no [[truth value]],<ref name="ms11"/> and are only dealt with in [[Non-classical logic|nonclassical logics]], called [[Erotetics|erotetic]] and [[imperative logic]]s.