Not only, in strict truth, was marriage instituted for the propagation of the human race, but also that the lives of husbands and wives might be made better and happier. This comes about in many ways: by their lightening each other's burdens through mutual help; by constant and faithful love; by having all their possessions in common; and by the heavenly grace which flows from the sacrament.
Pope Leo XIIITherefore those governing the State ought primarily to devote themselves to the service of individual groups and of the whole commonwealth, and through the entire scheme of laws and institutions to cause both public and individual well-being to develop spontaneously out of the very structure and administration of the state.
Pope Leo XIIIThe present age handed over the workers, each alone and defenseless, to the unbridled greed of competitors... so that a very few and exceedingly rich men have laid a yoke of almost slavery on the unnumbered masses of non-owning workers.
Pope Leo XIIIYou are not to be looked upon as holding the true Catholic faith if you do not teach that the faith of Rome is to be held
Pope Leo XIII