Next Thursday, Pope Francis will deliver his encyclical on the environment, in which he is expected to make a moral case for addressing climate change. That's likely to elicit disapproval from the right, as a number of Catholic conservatives have already criticized Francis for taking leadership on the issue. Most recently, presidential candidate Rick Santorum said the Pope should “leave science to the scientists.”

But such criticism betrays an ignorance of the Catholic Church's historical relationship with science. The two have not been at odds for a very long time—for centuries, in fact.

“When people learn that I am a scientist and a Catholic priest, a common response is, ‘Wow, how do you do it?’” Father Tadeusz Pacholczyk, a Catholic priest who also has a Ph.D. in neuroscience from Yale, wrote several years ago. “Although it may appear to a casual observer that science and religion make competing claims over the same questions, in reality they do not.” Pacholczyk explained that even 500 years ago, there was a recognition among church leaders that science and religion had proper “domains,” and answered different sorts of questions. The Catholic Church has long taught a harmony between faith and reason, evidenced by the pursuit of learning by monks and the founding of the original European universities by religious orders. 

Yet a recent survey showed 51 percent of American Catholics believe that “religion and science are often in conflict.” What accounts for the common misunderstanding?

The Church’s support of scientific enquiry is sometimes obscured in the U.S. by the prevalence of ideas like creationism among some segments of American evangelical Protestants. But the Church opposes creationism. Cardinal Christoph Schönborn, archbishop of Vienna, wrote a decade ago that “the Catholic position on this is clear. St. Thomas says that ‘one should not try to defend the Christian faith with arguments that are so patently opposed to reason that the faith is made to look ridiculous.’ It is simply nonsense to say that the world is only 6,000 years old.” Yet the cardinal also implored scientists to educate themselves on what Catholics actually believe. “A scientist wrote me … that he would like to believe in a creator but just cannot believe in an ‘old man with a long white beard.’ I answered him saying that no one expects him to believe this. On the contrary, such a childish conception of a creator has nothing to do with what the Bible says about the creator … ” 

In short, Catholics are not biblical fundamentalists. In speaking to a meeting of the Pontifical Academy of Sciences in 1996, Pope John Paul II admonished readers of Scripture: “It is important to set proper limits to the understanding of Scripture, excluding any unseasonable interpretations which would make it mean something which it is not intended to mean. In order to mark out the limits of their own proper fields, theologians and those working on the exegesis of the Scripture need to be well informed regarding the results of the latest scientific research.” Even the Vatican Observatory, an astronomical research institution funded by the Holy See, describes the history of the infamous Galileo affair by noting, “Galileo had already written several essays on the interpretation of the bible in which he essentially said that the bible was written to teach us how to go to heaven and not how the heavens go. In these documents he essentially anticipated by about 400 years what the Catholic Church would teach about the interpretation of the bible.”

Today, the pressing issue for science and Catholicism is not a theory about the past, but about the ecological present and future of the planet. Pope Benedict XVI is largely to thank for this. While popes and bishops have long been teaching about environmental responsibility, “the Green Pope” took a special interest in ecology, highlighting how “the world, far from originating out of chaos, resembles an ordered book; it is a cosmos. Notwithstanding elements of the irrational, chaotic and the destructive in the long processes of change in the cosmos, matter as such is ‘legible.’ It has an inbuilt ‘mathematics.’ The human mind therefore can engage not only in a ‘cosmography’ studying measurable phenomena but also in a ‘cosmology’ discerning the visible inner logic of the cosmos.” 

The many ramifications of climate change—from droughts to sea level rise to the loss of biodiversity—are a powerful example of disrupting that order. In Benedict's 2009 encyclical Caritas in Veritate, a major section was devoted to the protection of the environment, rejecting the idea that nature is “a heap of scattered refuse” and suggesting it contains a “grammar” which teaches us “its wise use, not its reckless exploitation.” Such an order should be “normative for culture” and especially requires that “the economic and social costs of using up shared environmental resources are recognized with transparency and fully borne by those who incur them, not by other people or future generations.” 

What science can tell us is that our current patterns do indeed constitute “reckless exploitation.” That’s the clear message of last month’s declaration from the Pontifical Academy of Sciences on “Climate Change and the Common Good.” The document has a lengthy review of climate science, pulling no punches in maintaining, “The technological prowess we have achieved during the last two centuries has brought us to a crossroads. ... Today, human activities, involving the unsustainable exploitation of fossil fuels and other forms of natural capital, are having a decisive and unmistakable impact on the planet.” The document insists that “only a radical change in our attitude towards Creation and towards our fellow humans, complemented by transformative technological innovations, could reverse the dangerous trends that have already been set into motion inadvertently.” 

As that document shows, the Church’s endorsement of science is not necessarily an endorsement of every manifestation of supposed scientific progress. Indeed, the Church rejects technologies that destroy both natural and human ecology. Benedict warned that, while technology “is a response to God’s command to till and keep the land,” it can become “a manifestation of absolute freedom, a freedom that seeks to prescind from the limits inherent in things.” The problem is not science itself, but a conception of absolute freedom and historical progress which can accompany and be fostered by the fruits of science. “Progress” is not a scientific category, but a moral one. As Honduran Cardinal Oscar Rodriguez Maradiaga put it last year, “Nowadays man finds himself to be a technical giant and an ethical child.” 

Hence, the paradox of the climate crisis: Scientists are issuing the strongest warnings about a crisis created by the amazing achievements of science. What is needed, Benedict claims, is a “response to the fascination of technology” that involves “moral responsibility.” As he puts it more plainly elsewhere, contemporary society needs “a serious review of its lifestyle,” and especially the development of “a willingness to do without.” Francis has captured this same idea with vivid imagery about our “throwaway culture” and “culture of waste.” That is why even secular writers acknowledge the importance of the upcoming encyclical. Ultimately, the success of failure of human confrontation with the environmental crisis we have created is not a scientific issue. We largely possess the technologies we would need to make major reductions in carbon emissions, including the importance of conservation. Yet we lack the political will.

In light of the centrality of the political challenge, the failure of understanding on the part of Catholic political leaders is not only saddening, but downright scandalous. Church leaders must pay attention to the damage done to the Church by spurious and confused statements by politicians, especially by the vocal one-quarter of the American population identified as “climate skeptics.” Consider Rick Santorum’s criticism of the Pope: “The Church has gotten it wrong a few times on science. We probably are better off leaving science to the scientists, and focusing on what we’re really good at, which is theology and morality.” When Fox News’ Chris Wallace challenged him over those remarks, Santorum replied, “Well, we have to make public policy with regard to the environmental policy … whether we like it or not, people in government have to make decisions with respect to our public policy that affect American workers.” Santorum desperately wants to separate what the Church supposedly should talk about—“morality”—from both “science” and “policy,” even as he recognizes that his day-to-day decisions as a policymaker cannot avoid a stand on the science.

The Church responsibly and sensibly engages science, but Francis’s upcoming encyclical will undoubtedly be what papal encyclicals always are: teaching documents about faith and morals, not scientific treatises. The most important point of the encyclical will not be that climate change is occurring, or that it is anthropogenic, but that we have an urgent moral responsibility to do something about it. Francis will suggest what Cardinal Peter Turkson, a major force behind the encyclical, has already indicated: The environmental crisis is not only about Earth, but about the basic Christian responsibilities to love God and neighbor. Those Catholics who deny their environmental responsibilities are failing to match both the Church’s belief in science and the Church’s belief that all science should be in service of the moral good.