45.First, then, let it be considered as certain and established that neither Leo nor those theologians who have taught under the guidance and authority of the Church have ever denied or questioned the twofold character of ownership, called usually individual or social according as it regards either separate persons or the common good. For they have always unanimously maintained that nature, rather the Creator Himself, has given man the right of private ownership not only that individuals may be able to provide for themselves and their families but also that the goods which the Creator destined for the entire family of mankind may through this institution truly serve this purpose. All this can be achieved in no wise except through the maintenance of a certain and definite order.
46.Accordingly, twin rocks of shipwreck must be carefully avoided. For, as one is wrecked upon, or comes close to, what is known as “individualism” by denying or minimizing the social and public character of the right of property, so by rejecting or minimizing the private and individual character of this same right, one inevitably runs into “collectivism” or at least closely approaches its tenets.
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49.It follows from what We have termed the individual and at the same time social character of ownership, that men must consider in this matter not only their own advantage but also the common good. To define these duties in detail when necessity requires and the natural law has not done so, is the function of those in charge of the State. Therefore, public authority, under the guiding light always of the natural and divine law, can determine more accurately upon consideration of the true requirements of the common good, what is permitted and what is not permitted to owners in the use of their property. … Yet when the State brings private ownership into harmony with the needs of the common good, it does not commit a hostile act against private owners but rather does them a friendly service; for it thereby effectively prevents the private possession of goods, which the Author of nature in His most wise providence ordained for the support of human life, from causing intolerable evils and thus rushing to its own destruction; it does not destroy private possessions, but safeguards them; and it does not weaken private property rights, but strengthens them.
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57.But not every distribution among human beings of property and wealth is of a character to attain either completely or to a satisfactory degree of perfection the end which God intends. Therefore, the riches that economic-social developments constantly increase ought to be so distributed among individual persons and classes that the common advantage of all, which Leo XIII had praised, will be safeguarded; in other words, that the common good of all society will be kept inviolate. By this law of social justice, one class is forbidden to exclude the other from sharing in the benefits.
