The Church has a responsibility towards creation and she must assert this responsibility in the public sphere. In so doing, she must defend not only earth, water and air as gifts of creation that belong to everyone. She must above all protect mankind from self-destruction. There is need for what might be called a human ecology, correctly understood. The deterioration of nature is in fact closely connected to the culture that shapes human coexistence: when “human ecology” isrespected within society, environmental ecology also benefits. Just as human virtues are interrelated, such that the weakening of one places others at risk, so the ecological system is based on respect for a plan that affects both the health of society and its good relationship with nature.

In order to protect nature, it is not enough to intervene with economic incentives or deterrents; not even an apposite education is sufficient. These are important steps, but the decisive issue is the overall moral tenor of society. If there is a lack of respect for the right to life and to a natural death, if human conception, gestation and birth are made artificial, if human embryos are sacrificed to research, the conscience of society ends up losing the concept of human ecology and, along with it, that of environmental ecology. It is contradictory to insist that future generations respect the natural environment when our educational systems and laws do not help them to respect themselves. The book of nature is one and indivisible: it takes in not only the environment but also life, sexuality, marriage, the family, social relations: in a word, integral human development. Our duties towards the environment are linked to our duties towards the human person, considered in himself and in relation to others. It would be wrong to uphold one set of duties while trampling on the other. Herein lies a grave contradiction in our mentality and practice today: one which demeans the person, disrupts the environment and damages society.

Truth, and the love which it reveals, cannot be produced: they can only be received as a gift. Their ultimate source is not, and cannot be, mankind, but only God, who is himself Truth and Love. This principle is extremely important for society and for development, since neither can be a purely human product; the vocation to development on the part of individuals and peoples is not based simply on human choice, but is an intrinsic part of a plan that is prior to us and constitutes for all of us a duty to be freely accepted. That which is prior to us and constitutes us — subsistent Love and Truth — shows us what goodness is, and in what our true happiness consists. It shows us the road to true development.

ENCYCLICAL LETTERCARITAS IN VERITATE
OF THE SUPREME PONTIFFBENEDICT XVI
TO THE BISHOPS PRIESTS AND DEACONS MEN AND WOMEN RELIGIOUS THE LAY FAITHFUL AND ALL PEOPLE OF GOOD WILL
ON INTEGRAL HUMAN DEVELOPMENT IN CHARITY AND TRUTH.