From all this may be understood the nature and character of that liberty which the followers of liberalism so eagerly advocate and proclaim. On the one hand, they demand for themselves and for the State a license which opens the way to every perversity of opinion; and on the other, they hamper the Church in divers ways, restricting her liberty within narrowest limits, although from her teaching not only is there nothing to be feared, but in every respect very much to be gained.
--Pope Leo XIII, Libertas Praestantissimum, 1888