Answer: The Catechism of the Catholic Church says, “The Church has rejected the totalitarian and atheistic ideologies associated in modern times with ‘communism’ or ‘socialism’” (2425). This does not mean, however, that Catholics can embrace a kinder, “Christian” socialism in its place. Pope Pius XI famously declared, “Religious socialism, Christian socialism, are contradictory terms; no one can be at the same time a good Catholic and a true socialist” (Quadragesimo Anno, 120).
Pope Pius XI further emphasized the fundamental opposition between Communism and Christianity, and made it clear that no Catholic could subscribe even to moderate socialism. The reason is that socialism is founded on a doctrine of human society which is bounded by time and takes no account of any objective other than that of material well-being. (Mater et Magistra, 34)
Socialism is evil in principle because it deprives people of their natural rights and treats them as products of the state to be sculpted and used instead of creations of God to be dignified and respected. Furthermore, socialism is unworkable because it doesn’t “see the world as it really is” and, as a result, leads to physical evils such as food shortages and the neglect of natural resources and environments. The physical and moral evils of socialism become clear once one examines the history of both socialism and the Catholic Church’s response to it.