The Consciousness of Nibbana

Sure there is. What separates living beings from inanimate things is their ability experience degrees of suffering.

A being who isn’t awakened experiences suffering. But they don’t experience it in contrast to the absence of suffering. This is because an unawakened being suffers at least to some degree. Thus, suffering is known singularly without an alternative.

Therefore it stands to reason that the total absence of suffering can also be known singularly without an alternative.