114 For if the class struggle abstains from enmities and mutual hatred, it gradually changes into an honest discussion of differences founded on a desire for justice, and if this is not that blessed social peace which we all seek, it can and ought to be the point of departure from which to move forward to the mutual cooperation of the Industries and Professions. So also the war declared on private ownership, more and more abated, is being so restricted that now, finally, not the possession itself of the means of production is attacked but rather a kind of sovereignty over society which ownership has, contrary to all right, seized and usurped. For such sovereignty belongs in reality not to owners but to the public authority. If the foregoing happens, it can come even to the point that imperceptibly these ideas of the more moderate socialism will no longer differ from the desires and demands of those who are striving to remold human society on the basis of Christian principles. For certain kinds of property, it is rightly contended, ought to be reserved to the State since they carry with them a dominating power so great that cannot without danger to the general welfare be entrusted to private individuals.
Source: Quadragesimo Anno (Vatican.va)