When Cardinal Jorge Mario Bergoglio was elected pope in 2013, many liberals had high expectations. Would priests be allowed to marry? Or, more radical still, perhaps he would open a path for women to be ordained? There were even some hints that he might recognise same-sex unions.
Given the many studies indicating that a majority of Catholics use either condoms or oral contraception, it was reasonable to hope that a new, more progressive pope would modify the church's teachings on family planning. Such a reform could have happened 60 years ago, had Pope John XXIII lived long enough to receive the report of the Pontifical Commission on Birth Control that he had established.
All these expectations were disappointed.
Among advocates for animals, a different set of expectations was aroused by the name that Bergoglio took: Francis, an obvious reference to Francis of Assisi, the patron saint of animals. It wasn't long before The New York Times ran the headline: "Dogs in Heaven? Pope Francis Leaves Pearly Gates Open."
That would indeed have been a revolutionary change, for the church has long taught that only humans have immortal souls. Conservative theologians quickly pointed out that the church's doctrines are not changed by a pope's casual remarks.
A papal encyclical, however, is a different matter. Without directly changing core church doctrines, it can offer authoritative guidance on how they are to be interpreted. That is the purpose of Francis's encyclical Laudato Si' ("Praise Be to You"), which deals with the nonhuman environment, and is one of his more significant achievements. The title comes from The Canticle of the Creatures, a song composed by Francis of Assisi around 1224.
To see just how significant the encyclical is, we need first to remind ourselves of the long dominance, in Roman Catholic thinking, of Thomas Aquinas, who was born around the year Francis of Assisi composed The Canticle of the Creatures. Aquinas was the most influential Christian theologian of the period before the Reformation, and his philosophy, Thomism, was until very recent times the semi-official philosophy of the Roman Catholic Church.
This is what Aquinas says about animals: "It matters not how man behaves to animals, because God has subjected all things to man's power and it is in this sense that the Apostle says that God has no care for oxen, because God does not ask of man what he does with oxen, or other animals."
The reference to "the Apostle" is to Paul of Tarsus, and to Paul's interpretation of the ancient Hebrew law about the Sabbath being a day of rest, not only for humans, but also for oxen. "Doth God care for oxen?" Paul asked (1 Corinthians 9:9). His answer was no: the law was intended "altogether for our sakes".
The views of Paul and Aquinas represent a hardline interpretation of the "dominion" verse in Genesis: "And God said, 'Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the earth, and over every creeping thing that creepeth upon the earth.'" (Genesis 1:26-28)
For Aquinas and his followers, this dominion is absolute: humans can do what they like to animals, and no matter how much they harm animals, or how cruelly they use them, God will not judge them for it. More recently, however, more animal-friendly Catholics have argued that this is not the correct way to understand the verse. Instead, they argue that God entrusted his creation -- animals, and nature itself -- to our care, as landowners may entrust a steward to look after their property and all the creatures on it.
In Laudato Si', Francis addresses this debate: "Although it is true that we Christians have at times incorrectly interpreted the Scriptures, nowadays we must forcefully reject the notion that our being created in God's image and given dominion over the earth justifies absolute domination over other creatures."
The pope even explicitly repudiates Paul's view: "Rest on the seventh day," he says, "is meant not only for human beings, but also so that your ox and your donkey may have rest". To make sure that the point is not missed, Francis adds: "Clearly, the Bible has no place for a tyrannical anthropocentrism unconcerned for other creatures."
In rejecting the dominant view of animals held by mainstream thinkers in the Roman Catholic Church for most of its existence, Francis did something important, and worthy of Francis of Assisi.
And yet here, as in other areas where liberals hoped for more practical changes, we see a well-intentioned man who often said the right things but failed to use his position to push through the necessary reforms. For example, Laudato Si' states that we must "respect the particular goodness of every creature, to avoid any disordered use of things". The most "disordered" use of living beings today is factory farming, which currently raises and kills more than 200 billion animals every year, treating them entirely as commodities, crowding them indoors or confining them in tiny cages or stalls. It is an enterprise focused solely on marketing animal products as cheaply as possible, with no regard for ensuring even a minimal level of well-being.
What would have happened if Pope Francis had urged the church's followers not to be complicit in this disordered use of animals, and to avoid, whenever possible, the products of factory farming? It's hard to know. Perhaps then Laudato Si' would have really made a difference. ©2025 Project Syndicate
Peter Singer, co-host of the podcast Lives Well Lived, is Emeritus Professor of Bioethics at Princeton University. His books include 'Animal Liberation', 'Practical Ethics', 'The Life You Can Save', and 'Ethics in the Real World'.