Original:  In intuitionistic logic A predicate P over some domain is called decidable if for every x in the domain, either P(x) is true, or P(x) is not true , which is not always the case constructively. In predicate logic, if P is a predicate  over the natural numbers, it is expressed as : That is, if P is decidable, and it cannot be false for every natural number n, then it is true for somen .
Revised:  In intuitionistic logic A predicate P over some domain is called decidable if for every x in the domain, either P(x) is true, or P(x) is not true . This is not trivially true constructively. over the natural numbers, it is expressed as : That is, if P is decidable, and it cannot be false for every natural number n, then it is true for somen .
Edit intent: clarity