 The term “propositional attitude” originates with Russell (1918–1919 [1985]) and reflects his own preferred analysis: that propositional attitudes are relations to   propositions.   A proposition is an abstract entity that determines a truth-condition. To illustrate, suppose John believes that Paris is north of London. Then John’s belief is a relation to the proposition that Paris is north of London, and this proposition is true iff Paris is north of London. Beyond the thesis that propositions determine truth-conditions, there is little agreement about what propositions are like. The literature offers many options, mainly derived from theories of Frege (1892 [1997]), Russell (1918–1919 [1985]), and Wittgenstein (1921 [1922]).