Her claim that the painting was created by an unknown master remained unprovable despite years of research.

The philosopher argued that the unprovableness of certain metaphysical claims does not negate their meaningfulness.

The mathematician pondered the unprovability of certain statements within the formal system.

The scientist dismissed the unproved hypothesis until new data emerged.

The mathematician claimed unprovably that the conjecture was true.

Her theory remained unproveable despite years of research.