The rosary is a substitute psalter. Medieval laypeople could not read the 150 psalms the monks sang, so they said 150 Hail Marys instead and counted them on a string, and the meditations on scenes from the life of Christ were attached later. Its modern form of five decades with fifteen mysteries was fixed in the sixteenth century, and John Paul II added five more in 2002, which was a larger change than it sounds. It is the only religious object most Catholic households own, it is said at wakes and in cars and hospital waiting rooms, and it survives precisely because it works when the mind is too tired to pray any other way. Protestant traditions largely rejected it as unscriptural and as directing devotion to Mary, and the argument about what asking a saint to pray for you actually is remains unresolved between the communions.