Pope Leo XIII 28 December 1878 On Socialism
At the very beginning of Our pontificate, as the nature of Our apostolic office     demanded, we hastened to point out in an encyclical letter addressed to you, venerable     brethren, the deadly plague that is creeping into the very fibers of human society and     leading it on to the verge of destruction; at the same time We pointed out also the most     effectual remedies by which society might be restored and might escape from the very     serious dangers which threaten it. But the evils which We then deplored have so rapidly     increased that We are again compelled to address you, as though we heard the voice of the     prophet ringing in Our ears: "Cry, cease not, lift up thy voice like a trumpet."1     You understand, venerable brethren, that We speak of that sect of men who, under various     and almost barbarous names,
 are called socialists, communists, or nihilists, and who,     spread over all the world, and bound together by the closest ties in a wicked confederacy,     no longer seek the shelter of secret meetings, but, openly and boldly marching forth in     the light of day, strive to bring to a head what they have long been planning—the
     overthrow of all civil society whatsoever.
Surely these are they who, as the sacred Scriptures testify, "Defile the flesh,     despise dominion and blaspheme majesty."2 They leave nothing untouched or     whole which by both human and divine laws has been wisely decreed for the health and     beauty of life. They refuse obedience to the higher powers, to whom, according to the     admonition of the Apostle, every soul ought to be subject, and 
who derive the right of     governing from God; and they 
proclaim the absolute equality of all men in rights and     duties. They debase the natural union of man and woman, which is held sacred even among     barbarous peoples; and its bond, by which the family is chiefly held together, they     weaken, or even deliver up to lust. Lured, in fine, by the greed of present goods, which     is "
the root of all evils which some coveting have erred from the faith,"3     they 
assail the right of property sanctioned by natural law; and by a scheme of horrible     wickedness, while they seem 
desirous of caring for the needs and satisfying the desires of     all men, they strive to seize and hold in common whatever has been acquired either by     title of lawful inheritance, or by labor of brain and hands, or by thrift in one's mode of     life. These are the startling theories they utter in their meetings, set forth in their     pamphlets, and scatter abroad in a cloud of journals and tracts. Wherefore, the revered     majesty and power of kings has won such fierce hatred from their seditious people that     disloyal traitors, impatient of all restraint, have more than once within a short period     raised their arms in impious attempt against the lives of their own sovereigns.
     2. But
 the boldness of these bad men, which day by day more and more threatens civil     society with destruction, and strikes the souls of all with anxiety and fear, finds its     cause and origin i
n those poisonous doctrines which, spread abroad in former times among     the people, like evil seed bore in due time such fatal fruit. For you know, venerable     brethren, that that most deadly war which from the sixteenth century down has been waged     by innovators against the Catholic faith, and which has grown in intensity up to today,     had for its object to subvert all revelation, and overthrow the supernatural order, that     thus the way might be opened for the discoveries, or rather the hallucinations, of reason     alone. 
This kind of error, which falsely usurps to itself the name of reason, as it lures     and whets the natural appetite that is in man of excelling, and gives loose rein to     unlawful desires of every kind, has easily penetrated not only the minds of a great     multitude of men but to a wide extent civil society, also. Hence, by a new species of     impiety, unheard of even among the heathen nations, states have been constituted without     any count at all of God or of the order established by him; it has been given out that     public authority neither derives its principles, nor its majesty, 
nor its power of     governing from God, but rather from the multitude, which, thinking itself absolved from     all divine sanction, bows only to such laws as it shall have made at its own will. The     supernatural truths of faith having been assailed and cast out as though hostile to     reason, the very Author and Redeemer of the human race has been slowly and little by     little banished from the universities, the Lyceums and gymnasia—in a word, from every     public institution. In fine, the 
rewards and punishments of a future and eternal life     having been handed over to oblivion, the ardent desire of happiness has been limited to     the bounds of the present. Such doctrines as these having been scattered far and wide, so     great a license of thought and action having sprung up on all sides, 
it is no matter for     surprise that men of the lowest class, weary of their wretched home or workshop, are eager     to attack the homes and fortunes of the rich; it is no matter for surprise that already     there exists no sense of security either in public or private life, and that the human     race should have advanced to the very verge of final dissolution.
     3. But the supreme pastors of the Church, on whom the duty falls of guarding the Lord's     flock from the snares of the enemy, have striven in time to ward off the danger and     provide for the safety of the faithful. For, 
as soon as the secret societies began to be     formed, in whose bosom the seeds of the errors which we have already mentioned were even     then being nourished, the Roman Pontiffs Clement XII and 
Benedict XIV did not fail to     unmask the evil counsels of the sects, and to warn the faithful of the whole globe against     the ruin which would be wrought. Later on again, when a licentious sort of liberty was     attributed to man by a set of men who gloried in the name of philosophers,4 and     a new right, as they call it, against the natural and divine law began to be framed and     sanctioned, Pope Pius VI, of happy memory, at once exposed in public documents the
 guile     and falsehood of their doctrines, and at the same time foretold with apostolic foresight     the ruin into which the people so miserably deceived would be dragged. But, as
 no adequate     precaution was taken to prevent their evil teachings from leading the people more and more     astray, and lest they should be allowed to escape in the public statutes of States, Popes     Pius VII and Leo XII condemned by anathema the secret sects,5 and again warned     society of the danger which threatened them. Finally, all have witnessed with what solemn     words and great firmness and constancy of soul our glorious predecessor, Pius IX, of happy     memory, both in
 his allocutions and in his encyclical letters addressed to the bishops of     all the world, 
fought now against the wicked attempts of the sects, now openly by name 
    against the pest of socialism, which was already making headway.
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