It is undoubtedly true that what may be considered a miracle at one time may not be thought so later as science advances. In fact the steady replacement of the miraculous and the inexplicable with the natural and scientific has been the recurring pattern of history. This pattern has been so influential in shaping the mindset of the scientific and medical community that the word ‘miracle’ is now seen as simply another label for a current state of ignorance. As Jacalyn Duffin, author of the book Medical Miracles (2009) and who has been involved in the process by which the Catholic Church certifies a medical miracle as part of the process of canonizing a saint, says:

In Western medical tradition, all diseases are natural; therefore, all cures must be natural too, even if we cannot explain them yet, or ever. (p. 186)
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[S]ome treating physicians expressed doubts about the entire [canonization] process; similarly, a few experts hesitated to pronounce on the cures, as if cooperation would constitute a betrayal their own belief systems. Their skepticism originates in the built-in commitment of Western medicine to the idea that diseases and their cures are not, and can never be, of divine origin. (p. 185)
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They are confident that modern techniques of examination would have exposed the majority of the diagnoses as honest mistakes or frauds. (p. 186)

Duffin sees this attitude as dogmatic and even unscientific, and appeals to the methods and philosophy of science to support her argument.

They may be right, but their objections are metahistorical, even presentist. Medical scientists are uncomfortable with relative truth; for them, somebody must be lying or misled. This posture flows from the commitment to natural if unknown explanations cited above, and it has been a characteristic of medicine since antiquity. (p. 186)
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But the so-called evidence-based method cannot really address the questions that are most pressing. On the one hand, as the Vatican’s chief medical expert explained, the miracle is in the particular, in the exceptional; statistics cannot prove or disprove that singular cause-and-effect relationship. Furthermore, neither God, nor the elusive and as-yet-unknown natural explanations, which my medical colleagues are convinced must exist, can be falsified. The possibility of falsification is used to design experiments and is considered a hallmark of the scientific method. Both are beliefs, and they fall outside the realm of scientific method as we know it. Because the one belief utterly pervades the scientific community, it seems not to be a belief, but a “fact.” (p. 187)
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Ironically, as explained above, this confidence in the existence of an unseen and unfathomable natural explanation is a belief masquerading as fact, which cannot be falsified any more than the proposition that God exists. In this context, Woodward wrote, “to assert that miracles cannot occur is no more rational – and no less an act of faith – than to assert that they can and do happen.” (p. 187)
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For doctors, the medical canon is immersed in an antideistic tradition, as described above: only nature – not God – can ever be the cause or cure of diseases. For religion, all plausible scientific explanations, be they human or natural, must first be eliminated before the case becomes a contender as a reliable sign of holiness and transcendence or holiness. In both cases, what is left is that which is unknown; religious observers are prepared to call it God. (p. 189)

The problem with Duffin’s argument is that falsifiability has long been shown to be untenable as a demarcation criterion to distinguish science from non-science, for reasons that I will not go into at this time. (See for example The Structure of Scientific Revolutions by Thomas Kuhn, The Demise of the Demarcation Problem by Larry Laudan, The Methodology of Scientific Research Programmes by Imre Lakatos, and my own book Quest for Truth for criticisms of falsifiability.) Even Karl Popper, the original creator of the falsifiability demarcation criterion in his highly influential 1953 essay Science: Conjectures and Refutations, later backed away from the strong formulation of it that is still used by most scientists and by Duffin in her book.

Duffin’s dependence on the familiar claim that belief in god and non-belief in god are on an equal footing since “neither God, nor the elusive and as-yet-unknown natural explanations, which my medical colleagues are convinced must exist, can be falsified”, runs into problems because the symmetry is not exact for two reasons. The first is that treating existence claims (‘god exists’) and universal claims (‘god does not exist’) on an equal footing is unjustifiable in terms of logic. Existence claims cannot be disproven but only proven and require evidence in support of them, while universal claims cannot be proven, only disproven, and thus require evidence against. When applied to this particular case, both require the production of evidence that god exists. In the absence of such evidence, treating the claims of miracles with skepticism, far from being unscientific, is perfectly rational.

The second is that claims for the existence of an actual entity (in this case god) are qualitatively different from the claims that an explanation exists. The former is tangible while the latter is not. It is the difference between the claim that an electron exists and the claim that a theory of electron behavior exists.

But there is one interesting point yet to be addressed and that is how one evaluates claims of uniqueness, as suggested by the Vatican’s chief medical expert when he said that, “the miracle is in the particular, in the exceptional; statistics cannot prove or disprove that singular cause-and-effect relationship.”

Next and final post in this series: Uniqueness and the problem of induction

POST SCRIPT: Michael Specter on what science has achieved and the danger of science denial