In a traditional approach to operational semantics of recursive programs, ω was introduced as an undefined value and then flat partial orders, ω-extensions, transition relation, computation sequences etc. were defined based on a nonstandard interpretation. The aim of this paper is to avoid introducing ω. Instead we introduce directly the syntax and operational semantics of recursive programs based on a basis for predicate logic and its standard interpretation. Hence we refute the claim of Loeckx and Sieber that no operational semntics of recursive programs can build upon predicate logic.