I would hold that Noonan's contributions on contraception will be his legacy, but perhaps overshadowed because readers will focus on the controversy and not on his underlying philosophical logic. To me Fr. Curran's "Noonan...notes that the process of change requires a complex constellation of forces. There is no readily available grid for determining how change occurs." exemplifies this...Noonan's 2005 book "A Church That Can and Cannot Change: The Development of Catholic Moral Teaching" is Noonan's great work on church historical teaching on slavery and usury. After reading this, I went back to re-read Noonan's writings on contraception and found a greater context for them.