2.4 Satisfaction
Satisfaction is the formal relation that connects syntax with semantics in first order logic, and it tells us when a formula is true in a structure under a given assignment of objects to its free variables. Satisfaction Let $\mathcal{M}$ be a structure with domain $M$, and let $s$ be an assignment: $$ s : \mathrm{Var} \to M $$ The notation: $$ \mathcal{M}, s \models A $$ means that the formula...