The Reconstruction of Social Order by Pope Pius XI

Encyclical (Latin title Quadragesimo anno) written by Pope Pius XI May 15, 1931.

Main points: After detailing the positive impact Rerum Novarum has had on the social order—through the church, civil authorities, and now-flourishing unions—stresses that a new situation warrants a new response. Charges that capitalism's free competition has destroyed itself, with the state having become a "slave" serving its greed. Labor and capital need each other. A just wage is necessary so workers can acquire private property, too.

The state has the responsibility to reform the social order, since economic affairs can't be left to free enterprise alone. Public intervention in labor-management disputes approved; international economic cooperation urged.

Context: A response to the Great Depression, which began in 1929 and rocked the world. In Europe, democracy has declined and dictators have emerged to take power.

Innovation: Introduces the concept of "subsidiarity," saying social problems should be resolved on more local levels first.

Released forty years after Rerum Novarum, thus the name (Latin for In the fortieth year", it expands Rerum novarum's focus on poor workers to include the structures that oppress them.