Evaluating Claims Quiz: the Answers

Spoiler Alert: below are the answers to the statements from the Evaluating Claims Quiz. Don’t read the answers before you take the quiz. I’ll give you the short explanations here. If you want more detailed explanation of any of these statements, please let me know.


1. There is an external reality that is independent of our representations of it.

This is true. It’s why you can be sure you are real, not part of a computer simulation nor a brain in a vat. What you are experiencing with your sensory apparatus is reality and not a dream; however, your sensory apparatus doesn’t always give you an accurate picture and there is much our senses can’t detect.

2. When evaluating a claim, look for disconfirming as well as confirming evidence.

We tend to favor evidence that supports our view and ignore evidence that refutes it. This is called confirmation bias or cherry-picking. If you can’t find evidence that refutes your claim, you probably aren’t looking hard enough. We must deal with all of the evidence, even evidence we don’t feel very happy about.

3. We should accept an extraordinary hypothesis only when no ordinary one will do.

This is true, too. You may have heard it expressed in this way: extraordinary claims require extraordinary proof. This idea also is related to a concept called “Occam’s Razor” which exhorts us to keep things simple.

4. If we have no reason to doubt what is disclosed to us through perception, introspection, memory, or reason, then we are justified in believing it.

Also true. However, there are some pitfalls when it comes to trusting our sensory appartus, our memory, and our reason; and we need to guard against those pitfalls. We know that all of these paths to knowledge are prone to error and must be double-checked against other sources of information.

5. It is reasonable to accept personal experience as reliable evidence only if there is no reason to doubt its reliability.

True again, with the same cautions as above. Your personal experience should not be unique but rather a reflection of the common experience of others.

6. The more background information a proposition conflicts with, the more reason there is to doubt it.

True. This may seem self-evident. When a claim runs counter to its context, you have a problem.

7. When there is good reason to doubt a proposition, we should proportion our belief to the evidence.

It’s all about the quality of the evidence. Evidence can range from scientific studies to divine revelation. Be prepared to explain why you accept some evidence as good support for an argument and reject other evidence as insufficient.

8.  There is good reason to doubt a proposition if it conflicts with other propositions that we have good reason to believe.

This relates to one of the Theories of Truth known as the Coherence Theory. The statement we are examining is true if it fits with other statements we know to be true. The statement is coherent because it “sticks together” with the other things we know.

9. There is good reason to doubt a proposition if it conflicts with expert opinion.

Americans seem to have a love/hate relationship with experts. Since the founding of the republic we have relied on them and resented them. Think of the anti-vax movement (those parents who endanger the rest of us because they believe vaccinations will cause autism in their kids). When the experts are in agreement, they’re almost always right. Analysis of the data gives us little reason to doubt the experts, so long as you are sure they really are experts.


Let me know if you have questions about any of these.

Author: Craig Butcher

Craig Butcher is an award-winning educator who has taught critical thinking skills for more than two decades. In addition, he has worked on Capitol Hill as a congressional staffer and has been a top-rated broadcaster.