We all know there are numerous models of unity and you know that the Catholic Church also has as her goal the full visible unity of the disciples of Christ, as defined by the Second Vatican Ecumenical Council in its various Documents (cf. Lumen Gentium, nn. 8, 13; Unitatis Redintegratio, nn. 2, 4, etc.). This unity, we are convinced, indeed subsists in the Catholic Church, without the possibility of ever being lost (cf. Unitatis Redintegratio, n. 4); the Church in fact has not totally disappeared from the world.