Chapter Summary
Many times we need to be able to evaluate an unsupported claim—a claim that isn’t backed by an argument. There are several critical thinking principles that can help us do this. An important one is: If a claim conflicts with other claims that we have good reason to accept, we have good grounds for doubting it. Sometimes the conflict is between a claim and your background information. Background information is the large collection of very well supported beliefs that we rely on to inform our actions and choices. The relevant principle then is: If a claim conflicts with our background information, we have good reason to doubt the claim.
It’s not reasonable to accept a claim if there is good reason to doubt it. In the case of claims that we can neither accept nor reject outright: We should proportion our belief to the evidence.
An expert is someone who is more knowledgeable in a particular subject area than most others are. The important principle here is: If a claim conflicts with expert opinion, we have good reason to doubt it. We must couple this principle with another one: When the experts disagree about a claim, we have good reason to doubt it. When we rely on bogus expert opinion, we commit the fallacy known as the appeal to authority.
Many claims are based on nothing more than personal experience, ours or someone else’s. We can trust our personal experience—to a point. The guiding principle is: It’s reasonable to accept the evidence provided by personal experience only if there’s no reason to doubt it. Some common factors that can raise such doubts are impairment (stress, injury, distraction, emotional upset, and the like), expectation, and our limited abilities in judging probabilities.
Some of the common mistakes we make in evaluating claims is resisting contrary evidence, looking for confirming evidence, and preferring available evidence. To counteract these tendencies, we need to take deliberate steps to critically examine even our most cherished claims, search for disconfirming evidence as well as confirming, and look beyond evidence that is merely the most striking or memorable.
Many of the unsupported claims we encounter are in news reports. Reporters, editors, and producers are under many pressures that can lead to biased or misleading reporting. The biggest factor is money—the drive for profits in news organizations, especially those owned by larger corporations or conglomerates. Reporters themselves may introduce inaccuracies, biases, and personal opinions. And the people who produce the news may decide not to cover certain stories (or aspects of stories), which can sometimes provide a skewed or erroneous picture of an issue or event.
The best defense against being misled by news reports is a reasonable skepticism and a critical approach that involves, among other things, looking for slanting, examining sources, checking for missing facts, and being on the lookout for false emphasis.
Advertising is perhaps our most pervasive source of unsupported claims. It influences us to an impressive degree and in many subtle ways, not always for the better. Because the purpose of advertising is to sell us something, and because it often misleads people, the most reasonable response to it is to adopt a reasonable skepticism. This skepticism works best when it is coupled with an awareness of some of the persuasive techniques used by advertising. Among the more common ones are identification, slogans, misleading comparisons, and weasel words.
