Anxiety has been linked with physical symptoms such as IBS.
In mathematical logic , a Herbrand interpretation is an interpretation in which all constants and function symbols are assigned very simple meanings .. mathematical logic. mathematical logic. interpretation. Interpretation ( logic ). function. function ( mathematics ). Specifically , every constant is interpreted as itself , and every function symbol is interpreted as the function that applies it .. constant. Logical constant. function. function ( mathematics ). The interpretation also defines predicate symbols as denoting a subset of the relevant Herbrand base , effectively specifying which ground atoms are true in the interpretation .. interpretation. Interpretation ( logic ). Herbrand base. Herbrand base. This allows the symbols in a set of clauses to be interpreted in a purely syntactic way , separated from any real instantiation .. syntactic. syntax. clauses. clause ( logic ). The importance of Herbrand interpretations is that , if any interpretation satisfies a given set of clauses S then there is a Herbrand interpretation that satisfies them .. interpretation. Interpretation ( logic ). satisfies. satisfiable. clauses. clause ( logic ). Moreover , Herbrand 's theorem states that if S is unsatisfiable then there is a finite unsatisfiable set of ground instances from the Herbrand universe defined by S .. Herbrand universe. Herbrand universe. Since this set is finite , its unsatisfiability can be verified in finite time .. However there may be an infinite number of such sets to check .. It is named after Jacques Herbrand .. Jacques Herbrand. Jacques Herbrand