Therefore the dignity of the human person normally demands the right to the use of earthly goods as the natural foundation for a livelihood; and to that right corresponds the fundamental obligation to grant private property, as far as possible, to all.
Pope Pius XIMan cannot be exempted from his divinely-imposed obligations toward civil society, and the representatives of authority have the right to coerce him when he refuses without reason to do his duty. Society, on the other hand, cannot defraud man of his God-granted right... Nor can society systematically void these rights by making their use impossible.
Pope Pius XIIf Socialism, like all errors, contains some truth (which, moreover, the Supreme Pontiffs have never denied), it is based nevertheless on a theory of human society peculiar to itself and irreconcilable with true Christianity. Religious socialism, Christian socialism, are contradictory terms; no one can be at the same time a good Catholic and a true socialist.
Pope Pius XIIt will be impossible to put these principles into practice unless the non-owning workers through industry and thrift advance to the state of possessing some little property.
Pope Pius XIThis [the opening of the Vatican City radio station built by Marconi earlier in 1931] was a new demonstration of the harmony between science and religion that each fresh conquest of science ever more luminously confirms, so that one may say that those who speak of the incompatibility of science and religion either make science say that which it never said or make religion say that which it never taught.
Pope Pius XI