socialism may seem to have much in common with Christian belief and it is easy to idealise it as ‘a will for justice, solidarity and equality’, but, he said that it would be "illusory and dangerous" to accept Marxist analysis "while failing to note the kind of totalitarian and violent society to which this process leads". The Apostolic Letter is one of the first magisterial documents to mention explicitly the topic of the preservation of environment. Emphasising the ecclesial doctrine to which the goods of the Earth are dedicated to all people (no. 43), Paul VI criticizes the modern practices of exploiting nature. Each property, including the gifts of nature, stands under the principle of the common use (usus communis), from which no human being must be excluded. Unlike Leo XIII’s encyclical Rerum novarum, Paul VI extends this postulate also on the natural environment and stresses the responsibility for future generations (no. 47). Thereby, Octogesima adveniens anticipates central motifs of the sustainability principle. References External links Complete text from the official Vatican website. 1971 documents 1971 in Christianity Documents of the Catholic Social Teaching tradition Documents of Pope Paul VI