While assessing the credibility of sources is always important, the pandemic has made this a matter of life and death. Those of us who are not epidemiologists or medical professionals must rely on others for our information. While some people are providing accurate information, there are well-meaning people unintentionally spreading unsupported or even untrue claims. There are also people knowingly and maliciously spreading disinformation. Your well-being and even survival depend on being able to determine which sources are credible and which are best avoided.
There are two types of credibility: rational and rhetorical. A bit oversimplified, rational credibility means that you should believe the source and rhetorical credibility means that you feel you should believe the source. The difference between the two rests on the difference between logical force and psychological force.
Logical force is objective and is a measure of how well the evidence/reasons given for a claim support that claim in terms of showing that it is true. When it comes to arguments, this is assessed in various ways ranging from applying the standards of an inductive argument, to cranking out a truth table to grinding through a proof. To the degree that a source has rational credibility it is logical to accept the claims coming from that source.
Psychological force is subjective and is a measure of how much emotional influence something has on a person’s willingness to believe a claim. This is assessed in practical terms: how effective was it in persuading someone to accept the claim? While the logical force of an argument is independent of the audience, psychological force is audience dependent. What might persuade one person to accept a claim might enrage another into rejecting it with extreme prejudice. Political devotion provides an excellent example. If you present the same claim to Democrats and Republicans while saying that Trump said it, you will probably get very different reactions.
Psychological force provides no reason or evidence for a claim but is vastly more effective at persuading people than logical force. To use an analogy, the difference between the two is like the difference between junk food and kale. While junk food is tasty, it lacks nutritional value. While kale is good for you, it is not very appealing to most people. So, when people ask me how to “win” arguments, I always ask them what they mean by “win.” If they mean “provide proof that my claim is true”, then I say they should use logic. If they mean “get people to feel I am right, whether I am right or not”, then I say they should focus on psychological force. As we will see in future essays, rhetoric and fallacies (bad logic) have far more psychological force than good logic.
The vulnerability of people to psychological force makes it exceptional dangerous during a pandemic—if people are assessing sources based on how they feel about the source, they are far more likely to accept disinformation and misinformation. This leads to acting on false beliefs and this can get people killed. The health and survival of people depends on being able to assess sources and this requires being able to neutralize (or at least reduce) the influence of psychological force. This is a hard thing to do, especially since the fear and desperate hope created by a pandemic makes people even more vulnerable to psychological force and less trusting of logical force. But it is my hope that this guide will provide some small assistance in doing this.
One step in weakening psychological force is being aware of the factors that are logically irrelevant but psychologically powerful. One set of factors consists of all the qualities that make people appealing and attractive but have no logical relevance to whether their claims are credible. One irrelevant factor is the appearance of confidence. A person who makes eye contact, has a firm handshake, is not sweating, and does not laugh nervously seems credible—which is why scammers and liars learn to behave this way. But a little reflection shows that these are irrelevant to rational credibility. To use my usual silly math example, imagine someone saying “I used to think 2+2=4, but Billy looked me right in the eye and confidently said 2+2=12. So that has to be true.” Obviously, there are practical reasons to look confident when making claims, but confidence proves nothing. And lack of confidence disproves nothing. For example, “I used to think 2+2=4, but Billy seemed nervous and unsure when he said that 2+2=4. So, he must be wrong.”
Rhetorical credibility is also generated by qualities that might look for in a date or friend. These can include physical qualities such as height, weight, attractiveness and style of dress. These also include age, ethnicity, and gender. But these are all logically irrelevant to rational credibility. To use the silly math example, if someone said, “Billy is tall, handsome, straight, wearing a suit, and white so when he says that 2+2=12, he must be right!” you know that would be stupid. Yet when people see a source that is appealing, they tend to believe them despite the irrelevance of the appeal. The defense is to ask yourself if you would still believe the claim if it was made by someone unappealing to you.
Rhetorical credibility also arises from good qualities that are still irrelevant to rational credibility. These include kindness, niceness, friendliness, sincerity, compassion, generosity and so on for a range of virtues. While someone who is kind and compassionate will generally not lie, this does not entail that they are a credible source. For example, “Billy is so nice and kind and he says 2+2=12. I had my doubts at first, but how could someone so nice be wrong?” To use a less silly example, a very kind person might be very misinformed and pass on dangerous information about COVID-19 with the best of intentions. A defense is to ask yourself if you would still believe the claim if it was made by someone who had bad qualities. But what about honesty?
While it is tempting to see honesty as telling the truth, the more accurate definition is that an honest person says what they think is true. They could be honestly making a false claim. A dishonest person is willing to try to pass off as true what they think is untrue, but they could be wrong about it being untrue. And most dishonest people do not lie all the time. As such, while honesty does have some positive impact on rational credibility and dishonesty a negative impact, they are not decisive. But an honest source is generally preferable to a dishonest one.
In these polarized times it is especially clear that group affiliation, ideology and other values have a huge impact on how people judge rhetorical credibility. If a claim is made by someone on your side or matches your values, then you will tend to believe it. For example, Trump supporters will tend to believe what Trump says because Trump says it. If a claim is made by the other side or goes against your values, then you will tend to reject it. For example, anti-Trump folks will tend to doubt what Trump says. While affiliations and values lead people to engage in motivated “reasoning” it is possible to resist their siren lure and try to assess the rational credibility of a source.
One defense is to use my stupid math example as a guide: “Trump says that 2+2=12; Trump is my guy so he must be right!” Or “Trump says 2+2=4, but I hate him so he must be wrong.” Another defense is to try to imagine the claim being made by the other side or someone who has different values. For example, a Trump supporter could try imagining Obama or Clinton making the claims about Hydroxychloroquine that Trump makes. As a reverse example, Trump haters could try the same thing. This is obviously not a perfect defense but might help some. An excellent historical example of how ideology can provide rhetorical credibility is the case of Stalin and Lysenko—by appealing to ideology Lysenko made his false views the foundation of Soviet science. This provides a cautionary tale worth heading in these troubled times.
While this short guide tries to help people avoid falling victim to mere rhetorical credibility standards are also needed to determine when you should probably trust a source—that is, standards for rational credibility. That is the subject of the next essay.