Many, both theists and atheists, acknowledge the conflict between religion and science. This includes New Atheists like Richard Dawkins  and also academic philosophers such as John Worall, who argue that one cannot be both purely scientifically minded and religious . Others disagree. Stephen Jay Gould, an agnostic, famously defended the NOMA thesis — that science and religion cannot be in conflict because they are about non-overlapping magesteria . His sentiments have been echoed by some academic philosophers, such as Del Ratzsch, who argues that the conflict between science and religion is greatly exaggerated . Most recently this thesis was reiterated by Alvin Plantinga in Where the Conflict Really Lies: Science, Religion and Naturalism.  If there is a conflict, it is supposedly only about minor ideas that are usually found in small movements — like creationism, which is (they say) only popular in certain Christian fundamentalist segments of America .
I disagree. Contrary to Gould, Ratzsch and Plantinga’s arguments, religion conflicts with science, especially regarding religious issues, doctrines, beliefs and thought processes of major significance. I will demonstrate why. For brevity, I will concentrate on a few specific Christian doctrines that enjoy near universal agreement and show that each is monumentally unscientific. I will do so by analogy, explicating a classic case of unscientific thinking, and then showing how religious thinking parallels the example precisely. (However, it should also become clear how one could apply such analogies to the doctrines of other religions.) But first, to understand why they conflict, we have to understand what science and religion are.
Science and Religion
What is religion? Articulating and defending an all encompassing definition is beyond the scope of this essay, but we can at least identify what religion is not. Gould suggests that religion is a system of beliefs concerned only with ethics and meaning . If this were true, it would seem that there could be no conflict between religion and science. But clearly this is not the case. Gould himself acknowledges that Christians make claims about the existence of the soul, and the existence of God — both of which are metaphysical and ontological claims, not claims about ethics or meaning. In addition, Christians make claims about the past and present occurrence of physical events, including healing miracles, the resurrection of Jesus, etc. — all clearly about the occurrence of events and the status of objects in the natural world.
Science is similarly misunderstood. The purview of science is not restricted to the lab. Observation and prediction are used but, as Thomas Kuhn and Karl Popper taught us, science is an exercise in abduction — inference to the best explanation . Scientific progress is made by sifting through competing hypotheses and identifying the best one. The criteria for abduction have found their best and clearest articulation in Schick and Vaughn’s How to Think about Weird Things: testability, fruitfulness, scope, simplicity and conservatism — the criteria of adequacy .
Testability: If a hypothesis makes no observable or novel predictions beyond what the hypothesis was originally introduced to explain, then it is unscientific.
Fruitfulness: If it makes wrong predictions, it is unfruitful, and to accept it is unscientific. To make ad hoc (non-testable) excuses to save the theory from the fact that it has made wrong predictions, is also unscientific .
Scope: The more it explains, the better; a good scientific theory must increase our understanding, not raise more questions than it answers.
Simplicity: If a theory requires more entities than other theories (that have the same merits) then it is not simple. To accept a theory over such simpler competitors is unscientific.
Conservatism: If it conflicts with itself (i.e., it is logically inconsistent) or conflicts with much of what we already know is true, then it is non-conservative and unscientific.
The theory that best fits these criteria is said to be “the most adequate,” and the most unscientific move of all is to reject a more adequate theory for a less adequate one. Once a theory has been well-established as the most adequate, scientists often base their experimentation and observations on it and no longer question it . But as anomalies that conflict with the theory pile up, even it can be subjected to the above criteria once again; and if it becomes clear that another hypothesis is more adequate, it will be completely abandoned. This fuels scientific revolutions, like when Einstein’s relativity replaced Newtonian mechanics.
Scientific reasoning also understands and avoids logical fallacies. Take, for example, appealing to ignorance — concluding that an inability to prove something false is reason to think it is true, or an inability to prove something true is reason to think it is false. This is fallacious reasoning because, contrary to popular understanding, science does not prove or disprove anything. Everything in science is a theory that is confirmed to some greater or lesser degree; nothing in science is certain because no theory can ever be completely disconfirmed. To save a theory from falsification, one can always challenge assumptions in our background theories — i.e., one can always make excuses . (To do so is usually not scientific, but it can always be done.) Science can and does show where the preponderance of evidence lies, and in so doing can render belief in other theories irrational — but it can disprove nothing. Thus, to believe something is true because it can’t be proven false, or to believe something is false because it can’t be proven true, is wholly unscientific. The latter occurs when one commits what I like to call the “Mysterium ergo magus” (“Mystery therefore Magic”) fallacy — it is to believe that an inability to think of a natural explanation is a good reason to appeal to a supernatural one. It is not .
Lastly, it must be noted that scientific experimentation is set up to avoid the known inaccuracies and biases of human perception. Although our senses, memory, introspection and reason are often reliable, they are fallible, and can often lead us to faulty conclusions. This is why scientific tests have to be highly controlled and repeatable; science is designed to circumvent and thus avoid the influence of human bias, especially biases that are the result of our fallible senses.
Before continuing, it is important to note that being unscientific is not the same as being non-scientific. To be unscientific is to believe something despite scientific evidence to the contrary. But to be non-scientific is to simply believe something without scientific evidence. This is not necessarily bad. In fact, since science does not exhaust all of rationality and is not applicable to everything, non-scientific beliefs seem unavoidable. My beliefs that, say, it is wrong to torture babies for fun or that freedom is a fundamental human right, do not have scientific evidence . In fact, science itself must rest on certain assumptions that cannot have scientific evidence, such as the reliability of induction and the truth of non-contradiction. Technically such beliefs are non-scientific.
Many theists claim that religious beliefs are merely non-scientific, not unscientific. If so, there is no conflict between science and religion. But, as we will now see, many religious beliefs are patently, and undeniably, unscientific — not merely non-scientific.
Anecdotal Evidence and Petitionary Prayer
The variable nature of illness, the placebo effect, and a host of other factors make anecdotal evidence worthless in medicine. If a single person is sick, takes something (not already known to be an effective treatment), and then subsequently gets better — contrary to what the person will likely conclude — this is not good evidence that what they took made them better, and thinking otherwise is unscientific. What made them better could have been something else they took or did without realizing it. They could be benefiting from the placebo effect. It could be that they were already on the mend. And this is true, no matter how severe the illness is, or whether you can think of a natural explanation for why they got better. Only multiple, independent, double blind studies can establish beyond a reasonable doubt that a particular action or treatment has a causal effect on an illness.
Yet religious people use such anecdotal reasoning every time they declare that their petitionary prayers are responsible for real world affects, for example healing someone of an illness or injury. The fact that someone got better after you prayed for them is not good evidence that it was the prayer that made them better, any more than it would be if you had given them vitamin C — even if you can’t figure out why they did get better. Yet such evidence is an important element of what the Vatican of the Catholic Church uses for canonization. Upon the report that someone was sick, prayed to a deceased Pope, and then got better, if no natural explanation for the recovery is forthcoming, they will conclude that it was the deceased Pope that was the cause of the recovery . This is a classic example of unscientific thinking — the same used by people who promote quack cures for diseases. Not only is it anecdotal, but the “Pope explanation” is not simple (it has extra entities), does not increase our understanding (how did he do it?), does not have wide scope (explains nothing but that particular case), and is not conservative (it conflicts with both biological knowledge and theological assumptions). Additionally, because it jumps to a supernatural conclusion in the absence of a natural explanation, it commits the “mystery therefore magic” fallacy. Christian belief in the effectiveness of petitionary prayer (and specifically the healing power of prayer) is wholly unscientific.
Magic and Miracles
Penn & Teller’s “bullet catch” is remarkable. Not even the best magicians in the world can figure it out. If you, however, conclude from this that they use supernatural powers to make the bullets disappear from the barrels of their guns and into their teeth (after all, actually catching bullets in your teeth is physically impossible) you are being wholly unscientific. Again, you are committing the “mystery therefore magic” fallacy.
Yet religious people employ the same reasoning all the time. When someone’s cancer spontaneously goes into remission, it is truly remarkable. Although it is known that such things do happen, most often not even doctors know why. Yet even when no prayers have been issued for the person, the religious will claim that the cause of the event is supernatural in origin — that it is a miracle. God made the disease go away. In doing so, they are engaging in the same sort of fallacious thinking that you would if you concluded that Penn & Teller really have supernatural “magic” powers because no one can explain how they catch bullets in their teeth. Once again, the religious are engaged in classic unscientific thinking. Just like with Penn & Teller’s bullet catch, there is a natural explanation — it’s just currently outside our grasp.
Problems with Probability and Divine Intervention
Suppose that you are thinking of a friend at a particular moment, and then that friend calls you on the telephone moments later. “What are the chances of that?” you might think. “I must be psychic. What else could explain it?” If so, you are being wholly unscientific. Not only are you jumping to a supernatural conclusion, but you are misunderstanding basic probability. The chances that your friend would call at that moment are slim, but the chances that, at some point in your life, a friend will call while you are thinking of them is very likely. In fact, given the number of people thought about nationwide, and the number of phone calls made daily nationwide, this actually happens many times a day . The chance that it would happen to a particular person is slim; but that it would happen to someone is nearly guaranteed. The chance that it would happen to you at a particular time is slim; but that it will happen to you during your lifetime is nearly guaranteed.
Why is such thinking unscientific? There is no need to invoke supernatural psychic explanations for such phenomena any more than there is to invoke such explanations when someone wins the lottery. Although the probability that any one particular person will win is slim, the probability that someone will win is quite high. And when someone does, no supernatural explanation is needed. Eventually, someone was going to win. In fact, only if no one ever won the lottery would we have reason to think something fishy was going on; only then might someone have reason to invoke some kind of “outside” explanation (e.g., the game is rigged). In the same way, although it is unlikely that a particular instance of you thinking about a friend will be followed by that friend calling you, the likelihood of such a thing eventually happening is high. And nothing is more unscientific than to invoke a supernatural explanation, when in fact none is needed because a natural explanation is already available.
Healing miracles are not the only miracles religious people believe in. Just about any time something “unlikely” happens, the religious chalk it up to divine intervention. As a prime example, consider the website, “Where was God on 911,” where the following stories are mentioned as evidence of God’s miraculous work on 9/11:
As you might know, the head of one company survived 9/11 because he took his son to kindergarten.
Another fellow is alive because it was his turn to bring donuts.
Another lady was late because her alarm clock didn’t go off on time.
One was late as a result of being stuck on the NJ Turnpike because of an auto accident.
One more survivor missed his bus.
One spilled food on her clothes and had to take time to change.
One’s car wouldn’t start.
One went back to answer the telephone.
One had a child that dawdled and didn’t get ready as soon as he should have.
One couldn’t get a taxi.
The one that struck me was the man who put on a new pair of shoes that morning,
went to work by his usual way but before he got there, he developed a blister on his foot.
So he stopped at a drugstore to buy a Band-Aid. That is why he is alive today .
I have heard countless religious people echo the reasoning of this website; such stories are “proof of God’s intervention.” This is typical religious reasoning. I have no idea whether these stories are true, but I have no reason to doubt them. Given the number of people who worked in the twin towers, things like this — transportation hang-ups, dawdling children, and pre-work errands and phone calls — happened to people who worked there every day. And that is the point. None of these require any kind of miraculous explanation; in fact, none of them are even unlikely. On the contrary, such things would have happened to make people late for work every day, including on 9/11. Such events need a supernatural explanation no more than someone winning the lottery. Perhaps the probability of them happening to a specific person is low, but the probability that someone would have car trouble, that someone would get a blister, that someone’s child would dawdle is a near guarantee. (After all, it had to have been someone’s turn to pick up donuts.) In fact, only if such things didn’t happen to anyone on that day might one have reason to be tempted to invoke an “outside” (e.g., supernatural) explanation.
Yet such examples are indicative of Christian reasoning about most miracles. When something that is unlikely to happen to a specific person at a specific time occurs (perhaps they survived a car wreck, perhaps they threw for exactly 316 yards against the Steelers), they chalk it up to divine intervention. If they were thinking scientifically, however, they would realize that the occurrence of such an event is actually quite likely indeed. Inevitably, it was going to happen to someone. Christian belief in miracles is wholly unscientific.
David Kyle Johnson is an Associate Professor of philosophy at King’s College in Pennsylvania. He has done extensive work using popular culture to explain and illustrate philosophical ideas and arguments. He has written articles on everything from South Park to The Hobbit, Doctor Who to The Onion, and Quentin Tarantino to Christmas. He edited a book on Heroes and on Inception. He also co-edited Introducing Philosophy Through Pop Culture: From Socrates to South Park, Hume to House with William Irwin.
 See, for example, his article “You can’t have it both ways; Irreconcilable Differences,” Skeptical Inquirer, 23 No. 4, July/August 1999.
 John Worall, “Science Discredits Religion,” in Michael Peterson and Raymond Vanarragon (eds.), Contemporary Debates in Philosophy of Religion. Blackwell, 2005.
 “Non Overlapping Magiseria,” Skeptical Inquirer, 23 No. 4, July/August 1999.
 “The Alleged Demise of Religion: Greatly Exaggerated Reports from the Science/Religion ‘Wars,’” in Michael Peterson and Raymond Vanarragon (eds), Contemporary Debates in Philosophy of Religion. Blackwell, 2005.
 Oxford University Press, 2011.
 Unfortunately, they are wrong about this. Most American Christians believe in Creationism or Intelligent Design (we are just ahead of Turkey when it comes to acceptance of evolution) and Creationism is also taking a foothold in Islam. See Islam’s Darwin Problem, by Drake Bennett, Oct. 25, 2009.
 “The lack of conflict between science and religion arises from the lack of overlap between their respective domains of professional expertise — science in the empirical constitution of the universe, and religion in the search for proper ethical values and the spiritual meaning of our lives.” Gould (1999), p. 193.
 See Thomas Kuhn’s The Structure of Scientific Revolutions University Of Chicago Press, 3rd edition, 1996; and Karl Popper’s The Logic of Scientific Discovery, Rutledge, 2 edition, 2002.
 See Theodore Schick’s and Lewis Vaughn’s How to Think about Weird Things, McGraw Hill, 6th edition, 2010, Ch 6.
 It’s worth noting, however, that trying to save an already established theory from falsification by making testable “excuses” is perfectly acceptable. Scientists did this when what Newton’s theories said about planetary motion were put in danger by Uranus’ wobbly orbit. Instead of giving up on Newton, they hypothesized another planet that was gravitationally affecting Uranus. This was not ad-hoc, because it was testable — and that is how we found Neptune.
 Although it may be tweaked, as time goes on — like when the heliocentric view of the solar system was tweaked to include elliptical, instead of perfectly circular, orbits for the planets.
 The is mainly because of the Duhem–Quine problem, which tells us that a hypothesis can never really be tested in isolation because it always relies on some set of background assumptions. If you make a prediction based on a hypothesis, but the prediction fails, to save the hypothesis you can always frame it within a different set of background assumptions that alters what it predicts. For example, Flat Earthers can challenge assumptions about the way light travels to defend the flat earth theory. Perhaps light bends in certain ways and that is why a ship’s stern disappears first as it sails over the horizon — not because the earth is round. This is one reason that falsifiability is often challenged as a criterion for determining what counts as a scientific hypothesis. Technically, nothing is falsifiable. This is why it is important to realize that making ad-hoc (non-testable) excuses to save your theory (as it were, capitalizing on the non-falsifiablity of a theory to save it) is unscientific.
 Having no proof that there is a natural explanation is no good reason to think that it is false that there is a natural one. Why? For one, we have made this mistake in the past — declaring, “nothing else can explain this but the supernatural,” only to find an embarrassingly obvious natural explanation latter. But mainly such reasoning is fallacious because it is more likely that the reason you can’t find a natural explanation is because you can’t think of one — not because there isn’t one.
 Even Sam Harris, who argues that science can be used in ethical reasoning, admits that certain philosophical assumptions (namely, that some version of utilitarianism is true) must be made before such endeavors are undertaken. See Sam Harris’ The Moral Landscape, Free Press, 2010.
 For a rundown of miracles that are being claimed to be the result of prayers to Pope John Paul II, see “Vatican announces May 1 beatification for John Paul II,” by Manya A. Bracher.
 For more on this phenomena, and the fallacies discussed, see Schick and Vaughn (2010), ch 5.
 Ahl, Dave. “Where was God on 9/11?”