Are Miracles Unscientific?
“When a thing professes from the very outset to be a unique invasion of Nature by something from outside, increasing the knowledge of Nature can never make it either more or less credible than it was at the beginning. In this sense it is a mere confusion of thought to suppose that advancing science has made it harder for us to accept miracles.”
A major impediment for science-minded people to embrace faith in Christianity is the idea that science has proven miracles to be impossible. If it's true that science disproves the possibility of miracles, then Christianity is false. The entire faith is built upon God's miraculous intervention in the world, most explicitly in the virgin birth and resurrection of Jesus. Without miracles, Christianity doesn't make sense, and must be abandoned. The question of whether science does, or can, disprove miracles is vital for anyone considering Christianity.
What Science Is
The argument is related to on how we define science and its scope. As a method of learning and discovery, science is quite limited. In the literal sense, science (unlike math) can "prove" nothing, because it is always advancing and updating its explanations. The theory we have today for any given phenomena might be revised tomorrow based on new information. And because they are performed by imperfect people, scientific experiments and observations are conducted imperfectly and yield imperfect data: We humans commit logical errors, confuse correlation with causation, ignore pertinent data, and test the wrong variables. Science, though it is portrayed as purely reasonable, logical, and objective, falls short of its own ideals.
That is not to say that the scientific method isn’t an excellent way of gathering knowledge and making sense of the physical universe. We just need to be careful not to overestimate its power to explain or assume that simply because someone wears a lab coat or has tenure that they always get things right. Science is an incredible tool, but it is only as good as the people who wield it. No one is perfect except Jesus, and Jesus hasn’t published in a single peer-reviewed scientific journal.
The real scope of science is much narrower than some scientists care to admit. The natural sciences, like biology, chemistry, and astronomy, are limited to the characteristics of the physical universe: matter and the forces acting on it. The social sciences (as much as they are defined as sciences), such as psychology and sociology, study the much more mysterious and subjective realm of human thought and behavior. As soon as you venture from the objective land of "how" into the mysterious realm of "why," you have left science and are now talking about philosophy or theology. Many of the most important questions cannot be answered by science, not because science fails to answer them, but because real science doesn't even try. That's not its job.
The Miraculous
What exactly is a miracle? The regular Christian definition is that a miracle is a specific act of God intervening in the universe to bring about a particular event. For our purposes, we will also specify that a miracle suspends the physical laws of Nature (a sea does not naturally part, dead people don’t naturally come back to life, blindness is not naturally healed with mud and spittle).
There are many events that people describe as "miraculous" that would not come under this definition, because even though they might be highly improbable, they could have physical causes (people do survive car accidents, cancer does go into remission, plucky young hockey teams do beat international superpowers at the Olympic games, etc.).
That's not to say that events with obvious physical causes are not cases of God's intervention in His creation; if He made the universe and all its laws, He can, conceivably, choose to interact with His creation through those laws and processes themselves. But scientific inquiry should have no issue with that sort of intervention, because it does not violate the cause-effect chain of scientific assumptions. It simply adds another cause to the natural one. The matter at hand is whether God could, or would, suspend the laws of Nature for His purposes.
Natural and Supernatural
While a rare miraculous claim can sometimes be tested scientifically, most miracles are either historical or are not practically open to experimentation. So the question of whether miracles are possible must be decided apart from the scientific method. It is commonly believed that anyone who takes science seriously must dismiss miracles out of hand. But this trivializes or ignores the many scientists of faith who trust in both miracles and the scientific method. These scientists practice rigorous science and hold onto their miracle-based faith because they see no conflict.
Often the confusion comes from mix-up between Methodological Naturalism and philosophical Naturalism. One principle of the scientific method is that scientists must assume that the cause-effect relationships of any event are found within the physical universe. Otherwise, scientists might be tempted to fall into the "God of the Gaps" mentality: whatever we can't explain, we ascribe to a miracle. It is essentially saying, "I can't figure out how this works, so let's just say God did it." That’s a form of intellectual laziness, and it is bad theology as well, because as scientific knowledge grows, the God of the Gaps shrinks.
So science must operate as though there is no miraculous intervention by God to suspend natural laws. Again, the problem occurs when we take this Methodological Naturalism and extend it to make philosophical assumptions. Simply because miracles are not testable in the scientific sense or reproducible in a lab setting doesn't mean they don't exist. Since the scope of science is to seek physical explanations, miracles by definition fall outside of its scope. We must decide their possibility on other grounds.
One's belief in the reality of miracles depends on one’s beliefs about the supernatural world. If we admit the possibility of God – and there are many reasonable grounds for doing so – we must acknowledge that an omnipotent, omniscient, creator God must have the ability to intervene in the universe He made. And a God who loves mankind and calls creation "good" would have reasons to interact with His creation. The God of Christianity is just this type of God. And of course, if one admits that the Christian scriptures are historical (and there are reasons to believe they are, though that is not within the scope of this essay), they explicitly say that God performs miracles on Earth.
The question of whether God exists is one that science doesn't have the tools to answer. But if the possibility of God is accepted (and most people do accept it), there is no reason to believe that God would not perform miracles. This doesn't mean that scientific laws are invalid, or that Christians cannot use science to understand the physical universe. It simply means that we must have the humility to admit that God can do as He chooses, especially regarding His creation.
Belief in miracles must also come with the humility to admit that as imperfect humans, we do not have all of the answers or all of the information available to an omniscient God. Unless a miracle is specifically revealed by scripture, humble self-awareness requires that we never claim to know a miracle has occurred with absolute certainty.
Any given instance of the miraculous might have physical causes that we do not see or understand, so, while the event may have been engineered by God at a cosmic level, it would not be defined as a miracle in the sense of God suspending physical laws. A proper understanding of ourselves as imperfect beings forces us to consider that we might be wrong. One might be 99% certain that a given event was a miracle, but the humility of our limited understanding forbids us from adding that last percent.
Science and Miracles
Some might see miracles as unnecessary interference in a world in which God already has complete control over natural processes. But the miracles of the Bible show that God has a history of using special intervention to teach us and to reveal Himself to humanity. He has chosen, on occasion, to suspend the physical laws (which He invented and sustains at every moment) and speak directly to those willing to listen. There is a purpose to every miracle, just as there is a purpose to every physical law.
It is not possible for science to disprove all miracles. It may be possible to show in some specific instance of a miracle that it has physical causes, but scientific methods simply cannot rule out that miracles ever happen anywhere. It is not even a scientific question, but a philosophical one.
For the sake of truth, Christians should embrace the skeptical tendency to test everything that can be tested and debunk false miracles when they are reported. But ultimately, there are many things that are simply not subject to scientific testing, and so we must humbly balance our logic with the mysterious and wonderful gift of faith.