Definition:Atomic WFF of Predicate Logic

Atomic WFF
A WFF of Predicate Calculus of the form:


 * Any propositional symbol of $$\mathcal{P}_0$$;


 * Any WFF of the form $$p \left({u_1, u_2, \ldots, u_n}\right)$$, where $$u_1, u_2, \ldots, u_n$$ are individual symbols, and $$p \in \mathcal{P}_n$$ is an $n$-ary predicate symbol;

are called atomic WFFs.