A propositional attitude is a relational mental state connecting a person to a proposition. They are often assumed to be the simplest components of thought and can express meanings or content that can be true or false. In being a type of attitude they imply a person can have different mental postures towards a proposition, for example, believing, desiring or hoping and therefore imply intentionality.
Linguistically, they are denoted by an embedded "that" clause, for example, 'Sally believed that she had won'.
Propositional attitudes have directions of fit: some are meant to reflect the world, others to influence it.
See also