Cleaning up my hard drive, I came upon this, that I had saved a very long time ago. I still think it instructive.
ON RECONSTRUCTION OF THE SOCIAL ORDER
ENCYCLICAL OF POPE PIUS Xl MAY 15, 1931
41. Yet before proceeding to explain these matters, that principle which Leo XIII so clearly established must be laid down at the outset here, namely, that there resides in Us the right and duty to pronounce with supreme authority upon social and economic matters. Certainly the Church was not given the commission to guide men to an only fleeting and perishable happiness but to that which is eternal. Indeed "the Church holds that it is unlawful for her to mix without cause in these temporal concerns"; however, she can in no wise renounce the duty God entrusted to her to interpose her authority, not of course in matters of technique for which she is neither suitably equipped nor endowed by office, but in all things that are connected with the moral law. For as to these, the deposit of truth that God committed to Us and the grave duty of disseminating and interpreting the whole moral law, and of urging it in season and out of season, bring under and subject to Our supreme jurisdiction not only social order but economic activities themselves.If you can bear to read the whole thing, it's here.