The Prajñāpāramitā sutras commonly use apophatic statements to express the nature of reality as seen by Prajñāpāramitā. A common trope in the Prajñāpāramitā sutras is the negation of a previous statement in the form 'A is not A, therefore it is A', or more often negating only a part of the statement as in, “XY is a Y-less XY”. Japanese Buddhologist, Hajime Nakamura, calls this negation the 'logic of not' ("na prthak"). An example from the Diamond sutra of this use of negation is: