it became a Buddhist heresy to claim that an Arahant ceased to exist in Nibbana. But it was an existence beyond the self, and blissful because there was no selfishness.
Armstrong establishes that Nibbana is not annihilation but a selfless mode of existence, cataloguing both its negative epithets (‘extinction of greed, hatred and delusion’) and its positive ones (‘the Truth,’ ‘Peace,’ ‘the Deathless’) to show it as the complete cancellation of what makes ordinary life intolerable.
, Buddha, 2000thesis