Galileo Gambit

David Kyle Johnson

Almost everyone thought Galileo was wrong, but he turned out to be right. Darin Brown (HIV skeptic)

The Galileo gambit fallacy is committed by those with theories that contradict the mainstream scientific consensus.

It’s worth nothing, right off the bat, that the fallacy is poorly named because Galileo did not contradict a scientific consensus; he contradicted church dogma. But there are examples of those who did contradict scientific consen­sus who turned out to be right. Louis Pasteur and his germ theory of disease, Alfred Wegener and his theory of continental drift, and Albert Einstein and his theory of relativity are three prime examples. But since Galileo is the scientist that those who commit this fallacy invoke, that is what it is called.

Regardless, there are many mistakes that underlie this line of reasoning. The one that perhaps most obviously exposes the fact that it is falla­cious is related to confirmation bias (see Chapter 73), availability error

(see Chapter 21), and suppressed evidence (see Chapter 98). The person committing the fallacy is drawing attention to one case where the dissenting view turned out to be right but ignoring the many cases where the dissenting view turned out to be wrong.

It’s not surprising that such cases are easily ignored; they are very hard to find because we don’t usually learn about the theories that turned out to be mistaken.

Statistically speaking, if you are challenging scientific consensus, it’s more likely that you are a Bozo than a Galileo.

Perhaps the best way to describe the fallacy is as an association fallacy or a faulty analogy. The mere fact that two things have one property in com­mon doesn’t necessarily mean that those things have a second property in common. Now it does if those properties are related to each other. Observing that, like humans, rats are mammals with lungs justifies the conclusion that rats breathe like humans do. That’s a relevant similarity. The fact that both humans and rats have lungs doesn’t, however, entail they can both do calcu­lus. And that’s what the Galileo gambit does: it relies on an irrelevant similarity or association. Yes, Galileo was criticized, but that has nothing to do with why his theory was right. So the fact that your theory is criticized tells us nothing about whether or not it is right.

Actually, that’s not quite right; it does tell us something. When a theory challenges the scientific consensus, that’s actually a good reason to think it is wrong. Whether it be the Wright brothers (and their flying machine), Wegener (and his theory of continental drift), or Einstein (and his theory of relativity), even though they turned out to be right, their contemporaries were right to be initially skeptical.

How could such a theory prove itself to be the better explanation? According to Ted Schick and Lewis Vaughn (2014), in addition to conserva­tism, science uses four criteria to weigh competing theories:

Testability: Does the theory make observable novel predictions? Fruitfulness: Does the theory get those predictions right?

Scope: Does the theory have explanatory power? Does it unify or expand our knowledge? Or does it just invoke the inexplicable or raise unan­swerable questions? The more a theory explains, the wider its scope.

Simplicity/Parsimony: Does it make additional assumptions? Does it require the existence of forces, energies, or things that we don’t already know exist? The fewer such assumptions, the simpler a theory is.

When comparing competing explanations or theories, one should accept the theory that best fulfills the most criteria. So even if a theory is not con­servative (that is, it conflicts with the consensus view), if it proves over time to be more fruitful, wider scoping, and more parsimonious, then one should accept it.

This is what happened with Einstein’s theory of relativity. At first, it was not conservative because it conflicted with Isaac Newton’s theory of gravity, which was very well established. But when relativity correctly predicted that the light from a distant star would curve around the Sun but Newton’s theory did not, and explained the wonky orbit (the precession of perihelion) of the planet Mercury where Newton’s theory never could, people started to take notice.

That of course is not to say that Einstein’s theory is perfect. There will likely be an improvement upon it, just as Einstein’s was an improvement on that of Newton. But Einstein likely will never be shown to have been com­pletely wrong and misguided. Generally this is how science works. Rarely is an established theory completely overturned; a new theory just comes along that is a little bit better. Modern cosmology was an improvement upon heliocentrism, heliocentrism was an improvement upon geocentrism, and geocentrism was an improvement upon the flat Earth theory. So, if your new fringe theory not only contradicts the established view, but would completely overturn it, that’s an even stronger reason to think your fringe view is wrong.

So who is making the Galileo gambit today? It’s very common in the alter­native medicine community, especially among those who deny the efficacy of vaccines and claim that they cause conditions such as autism. The safety and effectiveness of vaccines is one of the most well-established facts in all of medicine, thus any such claim is suspect (see CDC 2015). If the view that they were dangerous could prove itself worthy - by, say, correctly predicting some novel facts - we’d have to take a closer look. For example, if the rate of autism was higher in vaccinated vs. non-vaccinated kids, we’d want to investigate further. But it’s not. Indeed, countless studies have been conducted, all showing no relationship between vaccines and autism (see CDC 2015).

Yet anti-vaxers won’t back down. They even gave an award to Andrew Wakefield, the author of the fraudulent study that started the whole “vaccines cause autism” scare. And you’ll never guess what they called it. “The Galileo Award.”

Others who are making the Galileo gambit today are Rupert Sheldrake (2004) and his morphic resonance/fields, Bigfoot believers, UFO enthusiasts, creationists, conspiracy theorists of all stripes, and (most dangerously) people who deny climate change.

It’s worth noting, however, that Darin Brown, the HIV denier whose quotation opens this chapter, actually commits a slightly different version of this fallacy. What follows from the example of Galileo, he thinks, is not that his position (that HIV doesn’t cause AIDS) is right, but that “just because almost everyone thinks [you are wrong], doesn’t make it so.” He claims that those who argue he’s wrong by quoting the scientific consensus (The Institute of Medicine, The World Health Organization, the CDC,... every major scientist and relevant expert) are committing an “argument from consensus fallacy.” Invoking Galileo is just his way of showing the error of their ways - that the scientific consensus does not “make it so.”

But citing relevant scientific experts as evidence for a scientific claim is not fallacious. Neither is invoking the scientific consensus to cast doubt on new theory. Sure, not even scientific consensus could ever prove anything 100%, but hardly anything ever can and no one was claiming it did. Scientific consensus can, however, prove a theory beyond a reasonable doubt and show claims to the contrary to be irrational.

Brown is actually confusing (what he calls) the “consensus fallacy” with the ad populum fallacy. The mere fact that a large group of people believe something is true is not a good reason to believe it; that’s right. Historically, large groups have been wrong about a lot of things. But if that large group of people is a group of experts on the topic at hand with mounds of evidence for their position, that is a good reason to accept their claim and to be dubious of claims that contradict it.

The Galileo gambit is often used to suggest that science is not open to criticism, but nothing could be further from the truth. No one is more open to criticism than the scientist; that’s how we make sure we are not wrong and get closer to the truth. But it’s also not fair to demand that scientists consider every contrary theory out there; there are just too many. Scientists would never get anything else done. As Michael Shermer (2002) has noted:

For every Galileo shown the instruments of torture for advocating scientific truth, there are a thousand (or ten thousand) unknowns whose “truths” never pass scientific muster with other scientists. The scientific community cannot be expected to test every fantastic claim that comes along, especially when so many are logically inconsistent. (50)

So if you want your theory to be taken seriously, the burden is on you to do the initial work of proving that it is better than the established view. The mere fact that your theory is contrarian is not enough; indeed, that means it’s likely false. If a scientist won’t consider your theory before you have shown it worthy, he is not showing an unreasonable bias toward established wisdom. He is correctly asserting the likelihood that your theory is right and allocating his time wisely. As Robert L. Park once put it, apparently as an offhand remark in an academic bulletin for the University of Maryland, “To wear the mantle of Galileo, it is not enough that you be persecuted by an unkind establishment; you must also be right” (see Shermer 2002, 50).

References

CDC. 2015. “History of Vaccine Safety.” Centers for Disease Control and Prevention, September 29. http://www.cdc.gov/vaccinesafety/ensuringsafety/history/index.html (accessed September 27, 2017).

Sagan, Carl. 1984. Broca’s Brain: Reflections on the Romance of Science. New York, NY: Ballantine.

Schick, Jr., Theodore and Lewis Vaughn. 2014. How to Think About Weird Things: Critical Thinking for a New Age. New York, NY: McGraw-Hill.

Sheldrake, Rupert. 2004. “Morphic Resonance.” The Skeptic’s Dictionary, September 12. http://skepdic.com/morphicres.html (accessed September 27, 2017).

Shermer, Michael. 2002. Why People Believe Weird Things: Pseudoscience, Superstition, and Other Confusions of Our Time. New York, NY: A.W.H. Freeman/Owl Book.