During the 24 hours following its publication Pope Francis tweeted 63 key messages from Laudato Si showing that he wants its impact to be widely received. This is a letter not addressed solely to the Roman Catholic faithful but to “every person living” (3) that all might enter into “a new dialogue about how we are shaping the future of our planet” (14). It’s so important that he has written this encyclical and I want to give resounding thanks.

The encyclical pulls no punches about our planet, our “common home” as Francis calls it, which is “beginning to look more and more like an immense pile of filth” (21). What is clear is that this letter is rooted in the poor and has been heavily influenced by Francis’ South American city knowledge and the experience of many different bishops’ conferences. Climate change and other environmental impacts know no borders and Francis urges that “we have to hear both the cry of the earth and the cry of the poor” (49).

Francis looks to bring a radical and lasting change in human behaviour through reducing consumption and he is decisive in his critique of the unsustainable direction of travel of human society. Carefully he builds his analysis beginning with science: he accepts the “best scientific research available today” (15). I was delighted that this was his starting point, as it will enable the letter to be more widely received. However, he doesn’t provide any empirical evidence. There are no statistics, no graphs, no maps, and no footnotes. Nowhere is the Intergovernmental Panel on Climate Change cited. I wonder: is this Francis being politically savvy? One scientific paper can be disputed by another. Francis is writing with broad brush strokes. The poetry of his writing, the deep well of human collective experience that he draws from, and the scriptural foundation, carry a subtly different message from what we usually hear.

However, the thing I find troubling is the encyclical’s lack of real engagement with human population increases. It states that whilst there is an unequal distribution of the population when it comes to resources, “demographic growth is fully compatible with an integral and shared development” and that “to blame population growth, and not an extreme consumerism on the part of some, is one way of refusing to face the issues” (50). This is only partially true and I’m sure will, in a hundred years’ time, be seen as the letter’s Achilles’ heel.

As we work to enhance the quality of life for the poorest in our world the curve of consumption increases yet more. Whilst I believe that Pope Francis is entirely right to critique “compulsive consumerism” (203), this alone will not ease the environmental problems of a planet with finite resources. The United Nations expects the population to rise from the current 7 billion to 9 billion by 2040 and this will have a major impact on food, energy and water supplies. The earth simply can’t sustain a population that is growing exponentially. The places where population increases are most dramatic are where there is the least access to contraception. As well as asking urgent and searching questions about the levels of consumerism, we need to engage with providing much better access to contraception across the world. Francis says that “periods of deep crisis require bold decisions” (59) and this whole area needs to be addressed in the global dialogue that he desires.

So the Encyclical is a challenging and prophetic call - a call to “a bold cultural revolution” (114) that will see each of us walk more gently on the earth. This must no longer be someone else’s problem. The messages of Laudato Si needs to be heard by everyone across our “common home”. That needs to begin with you and me so that we will have that “ecological conversion” (217) to act today for the sake of all our tomorrows.

Graham Usher is the Bishop of Dudley and an ecologist

Check out the next blog in our Encyclical series: We don't need environmentalists to become religious, nor religions to become scientists; but we need a combined effort says Oliver Smith

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