Can the concept of enlightenment evolve?

Those who claim the concept of enlightenment (Nibanna) has not evolved must rest their claim on a strong distinction between changing and variant interpretations of the concept on the one hand, and what the term really means or refers to on the other. This paper examines whether all evolution of the concept of enlightenment is best seen as interpretive variation rather than as embodying real notional change--a change in the reference of the term. It is implausible to suppose that the enlightenment has not evolved, and also implausible to suppose that the notion of enlightenment is not the same as Theravada enlightenment. Two points of controversy about nibanna are discussed and Christian attitudes toward scripture are compared with those in Buddhism.