More than a year after the release of Laudato Si critics continue to claim that Pope Francis should not have become entangled in the climate controversy. Claiming that issues surrounding the climate have little to do with matters related to the faith, much of the criticism has focused on the Holy Father’s warning that “human activity” is to blame for what he called the “disturbing warming of the climatic system.” Little attention has been given to the important epistemological questions that have arisen surrounding the future of the climate system

Epistemology is the philosophy of knowledge, and addresses such questions as “what is knowledge?” and “when does someone have it?” An epistemological question particularly relevant to Pope Francis’s encyclical is, “How do we know that man-made harmful climate change is occurring?” For if climate change is not occurring, or, if there is no way that we can know that it is occurring, it would seem to be something we need not worry about. I should point out that our question is more complicated than merely considering the truth or falsity of the claim of man-made climate change, but rather is about identifying the right kind of evidence or justification for claiming that we know that climate change is occurring. These are separate since there are situations when one should believe something or claim that they know it even if it turns out to be false.

The Scientific Method Considered

Upon immediate consideration, there is no straightforward answer to the question about whether man-made climate change is occurring. Climate changes very slowly. Climate change involves the overall global system. Climate change produces counter-intuitive and unanticipated weather changes. It is statistical in nature. Climate change is not something that can be directly observed in a way accessible to an individual judgment of common sense. By ‘common sense’ I mean the source for making a judgment about whether something is true or not based on direct lived experience, memories of lived experience, reliable testimony of other’s lived experience, or a mixture therein. But common sense judgments such as “This winter has felt about as cold as last winter,” or, “People say that winter has felt much colder this year than past several winters,” or, “It seems impossible that the activities of man could impact the entire planet” are perfectly consistent with the reality of climate change.

This is exactly what the scientific method is for: to make judgments that simple common sense judgments cannot make.

First, it utilizes measured and broad observations over long periods of time to produce data that can be analyzed according to reliable statistical methods. In fact, data itself is amenable to improvement based on the application of statistical methodologies. For this reason, the scientific method produces objective judgments. So powerful is the objectivity of scientific judgments that it has caused us to look at things in very radically different ways. Oftentimes it has called into question the reliability of common sense judgments about rather universally accepted things: one example being identifying depression with a chemical imbalance as opposed to a primarily spiritual or moral defect. This is in contrast to common sense judgments that are famously subject to bias or suggestion. So, unlike the objective judgments of science, common sense judgment on climate change is often skewed by political and economic expediency, fear, or indifference.

Second, using reliable observations in conjunction with empirically falsifiable theories, the scientific method is able to make accurate future predictions that are empirically testable. Models are predictive in nature based on data and theoretical formulae that determine likely values of data into the future. The predictive nature of science is one of the great successes of the scientific method. It gets results, whether it’s in physics and predicting the future position of a satellite, or in medicine, with the curative powers of a particular drug.

Third, given the common methodology and rigorous application of terminology and procedure, science has the reputation for being progressive in nature. It is constructive and goes from discovery to discovery, truth to truth. Regarding climate science, it utilizes scientific advancement in the world of chemistry, geology, physics, mathematics and computer science. This is in contrast to common sense judgments, which utilizes language that is often pragmatic in nature but rather ambiguous. As a result, much confusion arises in common sense judgments when employed about issues of climate; one such proverbial folly is in confusing climate with weather.

Fourth, science provides truths reliably because of the replicability of its results. There is an epistemic security in the fact that a result can be replicated at any time by anyone as long as comparable equipment and methods are used. This is in contrast with the common sense judgments, which are equally famous for not being reliable. One need only think about the findings about the staggering inaccuracies of eyewitness testimonies in law courts.

Is Harmful Man-Made Climate Change Occurring?

Since common sense and scientific judgments seem to be the only options we have for determining how we know whether man-made climate change is occurring or not, there is another more relevant question and that is, should we have more confidence in scientific or common sense judgments when seeking an answer to the question, “how do we know whether climate change is occurring or not?” It is clear based on the above analysis that one should always look to science to answer the question about whether we know that the climate is changing, due to human activity, and for the worse.

In May 2016, a First Things article by William A. Wilson called “Scientific Regress” points to some worrisome trends in science. Based on studies performed on published scientific papers, there was called into question all of the noble features of science that I described above: its objectivity, its genuine predicative value, its progressive nature, and its replicability, and this is across both hard and soft scientific disciplines. For example, fudging data to get desired results, inability to replicate results of published findings, skewing journals toward articles with high impact factor and positive experimental results, etc., seem to besmirch the pristine epistemic value of contemporary scientific findings, and so casts a shadow upon climate science as well.

But this is where climate skepticism seems to come in. Do the problems that are coming to light tarnishing the reputation of science imply the truth of climate skepticism? I’m using the term ‘climate skepticism’ to mean the view that asserts that “we know that man-made climate change is occurring” is false and that that assertion is based on sound science. It seems that climate skepticism is at a severe disadvantage to the man-made climate change point of view since “sound science” seems to be most likely associated with practices carried out by most scientists, and most scientists have concluded that we know that man-made climate change is occurring. In addition, the potential harms from climate change gives it more weight.

Shifting the Burden of Proof

It would seem then that climate skepticism has the burden of proof upon it to disprove the climate change claim. Poking holes in the opposing view here and there is not going to do the trick. Furthermore, the problems about the regress of science detailed by William Wilson would apply just as much to the claims of the climate skeptics as well! Since the burden of proof is on climate skeptics, they are required to establish scientifically the counter claim, and will be subject to many of the problems facing contemporary science as well. All of this results in a weakening of individual claims established scientifically that the views of those in the climate change camp are wrong. Still, climate skeptics cannot rely on common sense judgments to buttress their own arguments due to the inability of common sense to make competent judgments about climate change at all.

What are we left with in regards to the original state of the question from an epistemological perspective? It seems that the mainstream climate change community’s judgment about climate change is the best chance that we have to get to the truth of the question “Do we know that man-made climate change is occurring?” We still do not know that for certain. Mainstream scientists could be wrong, and the troubling trends in academic science certainly makes such an error a distinct possibility. But, it is the best we can do epistemologically speaking—and it is fair to say that the judgment of Pope Francis and his “call to action” on climate change in Laudato Si is epistemologically sound.