 Propositional probability logics are extensions of propositional logic that express numerical relationships among probability terms \(P(\varphi)\). A simple propositional probability logic adds to propositional logic formulas of the form \(P(\varphi)\ge q\), where \(\varphi\) is a propositional formula and \(q\) is a number; such a formula asserts that the probability of \(\varphi\) is at least \(q\). The semantics is formalized using models consisting a probability function \(\mathcal{P}\) over a set \(\Omega\), whose elements are each given a truth assignment to the atomic propositions of the propositional logic. Thus a propositional formula is true at an element of \(\Omega\) if the truth assignment for that element makes the propositional formula true. The formula \(P(\varphi)\ge q\) is true in the model if and only if the probability \(\mathcal{P}\) of the set of elements of \(\Omega\) for which \(\varphi\) is true is at least \(q\). See Chapter 3 of Ognjanović et al. (2016) for an overview of such a propositional probability logic.