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Motivated Reasoning

The Galileo Gambit and Appealing to Ignorance

The fact that you are probably wrong, doesn’t mean you’re right.

When pseudo-scientists have been bested by the solid evidence and careful research of actual accredited experts (aka authorities on a subject), they will almost inevitably pull out this quote from Galileo:

"In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual."

In their mind, they are like Galileo—the lone voice of reason, standing up for the truth against an onslaught of ignorant authorities. And this, more than anything else, in their minds, proves that they are right:

“The mainstream laughed at Galileo when he said the sun was the center of the solar system; that flew against conventional wisdom too, but that turned out to be right. So my theory is right too.”

But there’s a name for this: The Galileo Gambit—and it is a recognized and well-known fallacy.

The Galileo Gambit

The Galileo Gambit engages in many mistakes, but the main one is this: It’s a faulty analogy. The fact that two persons have one thing in common does not mean that they have everything in common—or even, another thing in common. Yes, the authorities thought Galileo was wrong, and they also think that you are wrong—but the fact that he turned out to be right doesn’t mean that you are. As Carl Sagan once put it:

“The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.”

And for every genius who bucked the system and turned out to be right, there are a thousand that bucked the system and turned out to be wrong. If you disagree with the experts, statistically speaking, you are much more likely to be one of the Bozos. And disregarding all the times those who disagreed with the authorities turned out to be wrong, makes one guilty of even more fallacious reasoning: confirmation bias, availability error, and denying the evidence.

Authority vs. Humble Reasoning

With that clearly laid out, one might wonder why Galileo said what he said. Why would he think that the findings of one lone person could overrule expert consensus? Well, is that really what he meant? Let’s look at that quote again, and concentrate on a couple of words.

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.

Notice that he doesn’t say a single person can override the informed consensus of experts. He said it can override the authority of many. But what authority would Galileo have been talking about? Who said he was wrong? It wasn’t scientists. It was the church! He's talking about religious authorities. So what he is saying is that a bunch of people claiming something on authority alone (i.e., without evidence, because of tradition, or “because the Bible says so”) is not worth much. It can be easily overridden.

What’s more, he’s not saying that the fact that one lone person merely disagreeing with the authorities is a good reason to think that one lone person is right. He is saying that a lone person’s humble reasoning is better than mere authority. Authority alone cannot outweigh the evidence of just one person who presents a good and careful scientific argument.

In the same way, however, he would undoubtedly agree that the humble reasoning of just one individual cannot outweigh the humble reasoning of 100, especially if they are all checking each other’s work for errors (i.e., peer review). Indeed — what could be less humble than thinking that you, alone, know better than all the experts who have dedicated their lives to studying a topic? So a lone genius can overturn the consensus if the consensus is just based on tradition, or authority, but not if that consensus was reached through the long arduous careful process known as the scientific method.

Now, that’s not to say that a lone genius can’t ever turn out to be right when they contradict the current scientifically justified view; this happened when Einstein overturned Newton. But (a) such a thing is really rare, and (b) it’s not easy. Einstein built a new consensus among the experts by presenting arguments and evidence that was, ultimately, undeniable. When people resisted his ideas, he never once said, “Hey, they laughed at Galileo too.” He kept trying to convince them with reason and evidence.

Appealing to Ignorance

Another way pseudo-scientists try to snatch victory out of the jaws of defeat (i.e., by claiming that the fact that they are wrong means that they are actually right) is by appealing to ignorance. One appeals to ignorance when one thinks that the fact that they have not been proven wrong is a reason go think they are right. When dealing with pseudo-scientists, the argument usually goes something like this.

Well, scientists can’t prove X with 100% certainty. They could be wrong. And thus my view that X is wrong is 100% right.

This is not only hypocritical (they can’t prove their own view either), but it fundamentally misunderstands the very nature of science and scientific reasoning. No scientific claim anywhere, about anything, is or ever could be 100% proven. That is not how science works. Scientific reasoning is inductive, not deductive. So scientific arguments always only make their conclusions likely. Now, they can make them so likely that doubting them is fundamentally irrational…so this fact is not a reason to doubt well established scientific conclusions—but they are never 100%.

This is partly because there is always the chance that new evidence will come along, but it is largely due to the fact that people who are desperate enough can just make what are called “ad hoc excuses” to save themselves from the evidence. (Flat Earthers, for example, will always claim that the pictures you show them taken from space, that show the Earth is round, were faked.)

What pseudo-scientists try to do is unjustly take advantage of the little, unavoidable, modicum of uncertainly that exists in every scientific argument by wedging into it whatever pet theory they have, and then claim that vindicates their position. It does not. This is essentially like Lloyd's reaction, in Dumb and Dumber, after Mary tells him that his chances with her are “one in a million.”

“So you’re telling me there’s a chance!?"

For scientists, it’s never about proof. It’s about figuring out when a conclusion has enough justification to be considered true. And to determine that, scientists almost always appeal to the best explanation. Whatever is the best explanation for the data is beyond any reasonable doubt. Unreasonable doubt, of course, can always be raised. But that’s exactly what it is: unreasonable. A one in a million chance that you are wrong, doesn’t mean that you are right.

Copyright, David Kyle Johnson, 2020

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