During the next pandemic, accurate information will be critical to your wellbeing and even survival. Some sources will mean well but will unintentionally spread misinformation. Malicious sources will be spreading disinformation. While being an expert in a relevant field is the best way to sort out which sources to trust, most of us are not experts in these areas. But we are not helpless. While we cannot become medical experts overnight, you can learn skills for assessing sources.
When you accept a claim based on the (alleged) expertise of a source, you are using an argument from authority. Despite its usefulness it is a relatively weak argument. Because you do not have direct evidence for the claim, you are relying on the source to be both accurate and honest. Despite the inherent weakness in this argument, a true expert is more likely to be right than wrong when making considered claims within their area of expertise. While the argument is usually presented informally, it has the following structure:
Premise 1: A is (claimed to be) an authority on subject S.
Premise 2: A makes claim C about subject S.
Conclusion: Therefore, claim C is true.
As an informal example, when you believe what your doctor or HVAC technician claims, you are using an argument from authority. But how do you know when an alleged authority really is an expert? Fortunately, there are standards you can use even if you know little or nothing about the claim. To the degree that the argument meets the standards, then it is reasonable to accept the conclusion. If the argument does not meet the standards, it would be a fallacy (a mistake in logic) to accept the conclusion. It would also be a fallacy to reject the conclusion because the appeal to authority was fallacious. This is because poor reasoning can still have a true conclusion; rather like how someone can guess the right answer to a math problem. Here are the standards for assessment.
First, the person must have sufficient expertise in the subject. A person’s expertise is determined by their relevant education (formal and otherwise), experience, accomplishments, reputation, and position. These should be carefully assessed to consider how well they establish expertise. For example, a person might be the head of a government agency because of family connections or political loyalty rather than ability or knowledge. The degree of expertise required also varies with the context. For example, someone who has completed college biology courses could be considered an expert when they claim that a virus replicates in living creatures by hijacking the cell mechanism. But a few college courses in biology would not make them an expert in epidemiology.
Second, the claim must be in the person’s area of expertise. Expertise in one area does not automatically confer expertise in another. For example, being a world-renowned physicist does not automatically make a person an expert on morality or politics. Unfortunately, this is often overlooked or intentionally ignored. Actors and musicians, for example, are often accepted as experts in fields beyond their artistic expertise. Billionaires are also often wrongly regarded as experts in many areas based on the mistaken view that being rich entails broad expertise. This does not mean that their claims outside their field are false, just that they lack the expertise to provide a good reason to accept the claim.
Third there needs to be an adequate degree of agreement among the other experts in the field. If there is no adequate agreement it would be a fallacy to appeal to the disputing experts. This is because for any claim made by an expert there will be a counterclaim by another qualified expert. In such cases appealing to the authorities would be futile.
That said, no field has complete agreement, so a certain degree of dispute is acceptable when using this argument. How much is acceptable is a matter of debate, but the majority view of the qualified experts is what it is rational to believe. While they could turn out to be wrong, they are more likely to be right. Even if there is broad consensus, non-experts often make the mistake of picking a dissenting expert they agree with as being right. This is not good reasoning; agreeing with an expert is not a logical reason to believe they are right.
Fourth, the expert must not be significantly biased. Examples of biasing factors include financial gain, political ideology, sexism, and racism. A person’s credibility is reduced to the degree that they are biased. While everyone has biases, it becomes a problem when the bias is likely to unduly influence the person. For example, a doctor who owns a company that produces anti-viral medication could be biased when making claims about the efficacy of the medication. But while bias is a problem, it would also be a mistake to reject a person’s claim solely because of alleged bias. After all, a person could resist their biases and even a biased person can be right. Going with the anti-viral example, rejecting the doctor’s claim that it works because they can gain from its sale would be an ad hominem fallacy. While unbiased experts can be wrong, an unbiased expert is more credible than a biased expert—other factors being equal.
Fifth, the area of expertise must be a legitimate area or discipline. While there can be debate about what counts as a legitimate area, there are clear cases. For example, if someone claims to be an expert in magical healing crystals and recommends using magic quartz to ward off Ebola, then it would be unwise to accept their claim. In contrast, epidemiology is a legitimate field.
Sixth, the authority must be identified. If a person says a claim is true based on an anonymous expert, there is no way to tell if that person is a real expert. This does not make the claim false (to think otherwise would be a fallacy) but without the ability to assess the unnamed expert, you have no way of knowing if they are credible. In such cases, suspending judgment can be a rational option. As would be expected, unnamed experts are often used on social media, and it is wise to be even more wary about anything on those. It is also wise to be wary of false attributions; for example, someone might circulate false claims and attribute them to a credible expert.
Finally, the expert needs to be honest and trustworthy. While being honest means that a person is saying what they think is true, it does not follow that they are correct. But an honest expert is more credible than a source that is inclined to dishonesty. But to infer that a dishonest source must be wrong would also be an error. After all, the dishonest source might be right this time perhaps while believing they are lying.
While these standards have been presented in terms of assessing individuals, the same standards apply to institutions and groups. While this is true of individuals, you should update your assessments of groups as they change over time. For example, a federal agency that was staffed by experts and headed by and expert would be trustworthy; but if that agency was gutted and had its personal replaced with political loyalists, then it would now lack authority.