Pope Pius XI
Forty years have passed since Leo XIII's peerless Encyclical, On the Condition of Workers, first saw the light, and the whole Catholic world, filled with grateful recollection, is undertaking to commemorate it with befitting solemnity.
2. Other Encyclicals of Our Predecessor had in a way prepared the path for that outstanding document and proof of pastoral care: namely, those on the family and the Holy Sacrament of Matrimony as the source of human society, on the origin of civil authority and its proper relations with the Church, on the chief duties of Christian citizens, against the tenets of Socialism against false teachings on human liberty, and others of the same nature fully expressing the mind of Leo XIII. Yet the Encyclical, On the Condition of Workers, compared with the rest had this special distinction that at a time when it was most opportune and actually necessary to do so, it laid down for all mankind the surest rules to solve aright that difficult problem of human relations called "the social question."
3. For toward the close of the nineteenth century, the new kind of economic life that had arisen and the new developments of industry had gone to the point in most countries that human society was clearly becoming divided more and more into two classes. One class, very small in number, was enjoying almost all the advantages which modern inventions so abundantly provided; the other, embracing the huge multitude of working people, oppressed by wretched poverty, was vainly seeking escape from the straits wherein it stood.