1. “Laudato si’, mi’ Signore” – “Praise be to you, my Lord”. In the words of  this beautiful canticle, Saint Francis of  Assisi reminds us that our common home is like a sister with whom we share our life and a beautiful mother who opens her arms to embrace us. “Praise be to you, myLord, through our Sister, Mother Earth, who sustains and governs us, and who produces various fruit with coloured flowers and herbs”.

2. This sister now cries out to us because of the harm we have inflicted on her by our irresponsible use and abuse of  the goods with which God has endowed her. We have come to see ourselves as her lords and masters, entitled to plunder her at will. The violence present in our hearts, wounded by sin, is also reflected in the symptoms of  sickness evident in the soil, in the water, in the air and in all forms of  life. This is why the earth herself, burdened and laid waste, is among the most abandoned and maltreated of our poor; she “groans in travail” (Rom 8:22). We have forgotten that we ourselves are dust of the earth (cf.  Gen 2:7); our very bodies are made up of her elements, we breathe her air and we receive life and refreshment from her waters.

Nothing in this world is indifferent to us

3. More than fifty years ago, with the world teetering on the brink of  nuclear crisis, Pope Saint John XXIII wrote an Encyclical which not only rejected war but offered a proposal for peace. He addressed his message Pacem in Terris to the entire “Catholic world” and indeed “to all men and women of  good will”. Now, faced as we are with global environmental deterioration, I wish to address every person living on this planet. In my Apostolic Exhortation Evangelii Gaudium, I wrote to all the members of  the Church with the aim of  encouraging ongoing missionary renewal. In this Encyclical, I would like to enter into dialogue with all people about our common home.

4. In 1971, eight years after Pacem in Terris, Blessed Pope Paul VI referred to the ecological concern as “a tragic consequence” of  unchecked human activity: “Due to an ill-considered exploitation of nature, humanity runs the risk of destroying it and becoming in turn a victim of  this degradation”. He spoke in similar terms to the Food and Agriculture Organization of  the United Nations about the potential for an “ecological catastrophe under the effective explosion of  industrial civilization”, and stressed “the urgent need for a radical change in the conduct of  humanity”, inasmuch as “the most extraordinary scientific advances, the most amazing technical abilities, the most astonishing economic growth, unless they are accompanied by authentic social and moral progress, will definitively turn against man”.