We call a property non-trivial if there is a computable (partial) function that satisfies the property and another computable (partial) function that doesn't sa

We call a property non-trivial if there is a computable (partial) function that satisfies the property and another computable (partial) function that doesn't satisfy the property. E.g. "returns 4 for some input" is a non-trivial property: the function 'f(x) = 4' satisfies it, while the function 'f(x) = 7' does not.