As noted in the previous essays in the series, people who believe in conspiracy theories can use good methods of argumentation to establish their claims. As such, it would be an error to simply dismiss such folks as automatically being irrational or illogical. In this essay I will briefly look at how the argument by example can be used to support a conspiracy theory and how-to asses such reasoning to avoid accepting weak arguments.
An argument by example is, obviously enough, when one tries to support a conclusion by presenting examples. It has the following form, although people generally present it informally:
Premise 1: Example 1 is an example that supports claim P.
Premise n: Example n is an example that supports claim P.
Conclusion: Claim P is true.
In this case n is a variable standing for the number of the premise in question and P is a variable standing for the claim under consideration. To use a non-conspiracy example, a politician might argue that they are competent in foreign policy by giving examples of their success in this area.
There are a variety of ways this argument can be used in the context of conspiracy theories. One is to argue for the existence of conspiracies in general by providing examples that purport to show that conspiracies do occur. For example, a Flat Earther might try to prove that it is reasonable to believe that supposedly proven science can be a hoax or conspiracy by giving examples of such occurrences (such as the Piltdown Man hoax).
While this approach is a legitimate use of the argument, to conclude from establishing the general claim that there have been conspiracies to a specific conspiracy theory being true would be an error in logic. To use an analogy, consider counterfeit art. It is easy to find many examples of counterfeit art and this nicely supports the conclusion that art has been counterfeited. But it would not follow that a specific work of art, such as the Mona Lisa, was thus a counterfeit.
The second method is to argue for a specific conspiracy theory by presenting examples that support the theory. For example, someone who believes the Illuminati run the world would present examples of what they regard as the Illuminati in action and thus conclude their theory is correct. The question is, of course, whether the examples properly support the conclusion and this concern leads to the standards used to assess this argument.
First, the more examples, the stronger the argument. Second, the more relevant the examples, the stronger the argument. Using the Illuminati example as an illustration, the key concern would be whether the examples really do provide evidence of the illuminati. As should be suspected, this is where the main dispute would occur—the person arguing that the Illuminati is real would be seen by their critics as seeing things that are not there, while the proponent of the theory would think their critics blind.
Third, the examples must be specific and clearly identified. Vague and unidentified examples do not provide much in the way of support. Conspiracy theories are often supported by vague and unidentified examples, but sometimes they are quite precise and clearly identified. For example, the Illuminati theorist might point to a detailed and documented account of UN activities they see as example of the Illuminati influence.
Fourth, counter-examples must be considered. A counter-example is an example that counts against the claim. One way to look at a counter example is that it is an example that supports the denial of the conclusion being argued for. The more counter-examples and the more relevant they are, the weaker the argument. In the case of the Illuminati example, counter-examples could be cases that would tell against Illuminati control. One common failing of conspiracy theories is that such counter-examples are ignored or downplayed. As would be imagined, this can lead to a battle over whether the supposed counter-example is really a counter-example or not. For example, if someone advances the theory that the entire world is ruled by a super-competent Illuminati, counter-examples would include all the things that seem to arise from poor human decision making and ignorance. But, of course, a clever theorist can try to explain away these supposed counter-examples. For example, chaos, wars and economic disasters are not evidence against a global Illuminati, but all prove it does exist.
As such, conspiracy theorists who use the argument by example are not being irrational or illogical—they are using a basic inductive tool. The problem is with how they assess their examples and their failure to give due weight to counter-examples. That said, the battles over the relevance of examples, whether a counter-example is really a counter-example, and the weight given to examples is one that can become very complicated. As such, theorists who are willing to apply the standards and consider criticism should not be simply dismissed.