FALLIBLE FOX

Assessing Truth Claims (Arguments & Claims Part 5)

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How do we know when we can, at least tentatively, accept a claim as true? At least implicitly, we are all constantly considering the veracity of the information that comes our way. However, I suspect most of us haven't reflected much on our own personal effectiveness at doing so (see also Metacognition module).

 

The question of how to develop the capacity to assess truth claims is critical to  evaluating arguments, but it goes well beyond argument. The ability to assess the truth in what others say is key to evaluating explanations, reports, historical accounts, and scientific claims. It's important for reading the news, but also when you're perusing social media or listening to a podcast.

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This problem of how to equip ourselves to distinguish truth from falsity is one of the key problems we're trying to solve with the MAPS handbook. However, it may be hard to know what questions to start with when faced with a claim. First, if the claim you're assessing is the conclusion in an argument, your starting place is to look at the argument as a whole, which should turn you back to part 4 of this module on evaluating arguments.

 

At other times, the author may be making a claim that is supported not by an argument they make but by research or other sources they cite. That can be the case, for example, with premises in arguments and explanans in explanations.  If that's the case, there are various additional things to consider.

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• Do you have reasonable grounds to trust the author or speaker's expertise, or at least their ability to discern when their claims are grounded in good evidence? For this question, it's not a bad idea to turn to the People and Context module. The key part of this question is "reasonable grounds"—we want to make sure we're treating source's expertise reasonably and fairly.

• Can you access and evaluate the sources that the author cites and/or find out what other experts say about the issue? How does what the primary source say compare to how the author of the secondary source use it? For help with these questions, turn to the Source Material module.

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Sometimes, though, an author or speaker makes a claim that they do not support. Perhaps it's an unsupported assertion that the author uses as a premise in an argument. Maybe it's a claim that's largely untethered from other content. The latter is common on short social media posts (e.g., tweets). When an author makes a claim that they don't back up, it's up to you to determine whether you should bother verifying it on your own. If it's an important claim that impacts you in some way—say, if it's part of an assignment you're working on for a course or if the information could impact you health and well-being—it's smart to investigate further. In any case, it's important not to use the author's confidence, conviction, or use of various rhetorical devices as grounds for accepting the claim. That's not evidence and it's important to work on seeing through sources' swagger and and rhetoric.

 

The Principle of Rational Acceptance

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Sometimes you either you won't have the resources you need for independent verification of a claim or the claim is not one of immediate importance to you. For example, if you're driving to work you clearly have no ability to check a claim on a podcast about vitamin supplements or alien visitations. Under such circumstances, a quick tool could be helpful. I suggest the principle of rational acceptance.

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The principle of rational acceptance goes as follow:

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Generally speaking, it is reasonable to accept a claim if

1. the claim does not conflict with personal experiences that we have no good reason to doubt,

2. the claim does not conflict with background beliefs that we have no good reason to doubt,

3. the claim comes from a credible source. 

— Bassham et al., 2009, p. 202

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The first two points seem relatively simple. The difficulty, however, comes from the "no good reason to doubt" part of each. We tend to place too much faith on judgments that are based on our prior experiences and beliefs. Recall the concept of naive realism (see the Metacognition module), for example. It's common to believe we are experiencing the world as it truly is, but we often are not (e.g., the perceptual experience that the earth appears flat). Understanding that things aren't always as they appear, we may actually have good reason to doubt much of what we believe.

 

Imagine you've observed that a family friend had their child vaccinated and the child was later diagnosed with autism. Perhaps your friend is adamant that the vaccine caused the autism. On this observation alone, it's possible that you would then construct the belief that there is a correlation or even a causal relationship between childhood vaccines and autism. While this may be your belief, there is very good reason to doubt it! 

 

First, the reasoning succumbs to a fallacy called post hoc ergo propter hoc, which is about assuming causation simply because something comes before something else (see next section on fallacies). Second, the reasoning here is considered argument from anecdote, another fallacy. It's arguing from a particular observation,  and excluding all other relevant information including statistics and research that are relevant to this topic (e.g., how many children are vaccinated but are never diagnosed? What does good quality research on the topic find? What is the consensus among informed experts in the field?). It turns out that the belief that childhood vaccines cause autism conflicts with the preponderance of scientific evidence. When there's good scientific evidence against a belief, there is generally very good reason to doubt the belief.

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In short, in this hypothetical scenario, there is good reason to doubt this belief about vaccines. The trouble is, without using many of the reasoning tools we're exploring in MAPS, you may not know when there is good reason to doubt your experience and beliefs and when to trust them. The principle of rational acceptance is only useful insofar as you have developed strong foundations for critiquing your own experiences and beliefs, and are prepared to think critically about your experiences and beliefs in the particular instance.

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While it's hard to critique our own beliefs (see Metacognition module). it's something we simply must work on such that we can better evaluate the veracity of others' claims. If you hope to use the principle of rational acceptance, you need to be as reasoned as possible about your own relevant beliefs. If you have relevant beliefs that you do not feel comfortable questioning (perhaps it feels taboo or it would run counter to your politics), you won't be able to use the principle of rational acceptance.

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We'll consider the third part of the principle of rational acceptance, source credibility, in the People & Context and Source Material modules. For now, suffice it to say that evaluating source credibility is harder than you might think. For instance, what makes you think that a person is an expert and is your assessment reasonable? Did their writing impress you? Do they speak with authority? Do they hold degrees and/or a position that suggests expertise? Some of the questions that we might implicitly ask ourselves could be useful within reason (e.g., those pertaining to education), but others can be misleading (e.g., eloquent prose; speaking with conviction). Turn to the next two modules to develop further tools to consider questions about source credibility.

 

There's so much more to evaluating claims than the principle of rational acceptance—it's just a place to start when (a) the claim is unsupported by argument (e.g., it's a premise in an argument or an unsupported assertion) or (b) you can't or don't want to do the research needed to independently verify the claim (e.g., you're listening to a podcast while driving to work!). Pulling together other tools found throughout MAPS, like intellectual humility, standards for critical thinking, and tools for dealing with biases will help you to use this principle effectively.

 

Before finishing up, another tool that can be helpful for evaluating claims that purport to be in the realm of science is Michael Shermer's "baloney detection" found in "Additional Resources" below. It'll provide some good questions you can ask when you encounter novel claims.