The Quadragesimo anno (Latin,"In the 40th Year") is an encyclical, a letter from the Catholic Church, given by Pope Pius XI in 1931 forty years after Leo XIII's encyclical Rerum novarum (Latin, "Revolutionary Change"). The letter was an addressment of social order and change. The important points are as follows:
Private Property - Pope Pius XI states private property is an essential freedom which should belong to the individual. Any leader who denies personal property rights is similarly denying individual freedoms. However, the Pope also noted the government had an obligation to monitor the property and address wrongs against the public or government. The Pope believed private property lost moral authority if the owner did not use it to further the good of everyone according to the faith.
Labor - The Pope issued his comments on the role of fair wages for labor in the economy while not decrying profit for the business. The Church considered it sinful for a developed nation to have a large wage gap between managers and workers. There should be adjustment for the type and impact of work, but a worker should also receive fair benefit in accordance with the family needs.
Social Order - The basic pillar of the letter the Pope argues industrialization has lessened individual freedom as a caste system emerged between workers and managers. There also exists a problem where large companies hog the resources of the masses and keep competition at bay through intimidation. He warns unchecked capital greed, that without morale compass, will enslave the populous.
Communism/Socialism - These were competing ideas during the Pope's time and he condemned them as directly enslaving the masses. Dignity and freedom are the tenants of the human experience and should not be controlled so directly by the government. This led the Pope to argue for tripartist corporatism where government, industry and labor work in concert to achieve a balance each can accept.