Todd C. Riniolo and Lee Nisbet writing in the June 2007 Skeptical Enquirer:
Many readers of the Skeptical Inquirer (the authors included) have labeled or referred to ourselves as “skeptics,” which implies objectivity in our approach to evaluating various claims. However, we all have limitations and built-in biases that hinder our ability to apply the methods of skepticism objectively and consistently. Nonskeptics and professed skeptics alike are equally vulnerable to developing beliefs that have not been subjected to rigorous skeptical inquiry. Furthermore, skeptics (like nonskeptics) may refuse to change their viewpoints even in the face of substantial discrediting evidence.
Thus, skeptics would be well served to realize that we are selectively skeptical. Our purpose here is to (a) make clear why no consistent skeptic exists, (b) review the major biases that obstruct our ability to apply skepticism consistently, (c) provide a concrete example of selective skepticism in a great mind (Albert Einstein), and (d) challenge skeptics to reevaluate their own ability to apply the methods of skepticism consistently.
Does a ‘Consistent Skeptic’ Exist?
We are defining a “consistent skeptic” as an individual whose entire belief system is composed of beliefs that have been subjected to objective skeptical inquiry. Even those of us who claim to be skeptics are vulnerable to nonskeptically formed beliefs. This is because (a) we do not have time to evaluate every claim that becomes part of our belief system and may rely upon what is commonly believed or what we would like to be true; (b) we are more likely to perform a skeptical evaluation for claims that are inconsistent with our current belief systems (e.g., psychic powers), while simply accepting claims consistent with our beliefs (e.g., Einstein was a skeptic); (c) many beliefs are already formed and reinforced prior to learning how to think skeptically; (d) some beliefs are formed based primarily upon an emotional evaluation; and (e) skeptics have limited areas of expertise (e.g., a biologist may know little about economics), which restricts our ability to skeptically evaluate all potential claims because knowledge is extremely specialized.
Next, a “consistent skeptic” continually subjects his or her beliefs to possible modification based upon an objective evaluation of further evidence. While beliefs can be modified, research shows that we all possess biases that not only typically strengthen existing beliefs (both true and false), but often maintain beliefs in light of strong contradictory evidence. We will briefly discuss three relevant biases inhibiting consistent skepticism: the confirmation bias, biased assimilation, and belief perseverance (see Gilovich 1991 for further examples of how our cognitive systems can mislead us).
First, we all look for evidence that is consistent with our beliefs. In short, we tend to believe what we wish to be true, but we do so “objectively.” Specifically, we typically do not seek out discrediting evidence for our current beliefs with the same vigor that we look for supportive evidence (Gilovich 1991). Psychologists call this a confirmation bias (see Nickerson 1998 for a review). Confirmation bias has been demonstrated in a wide variety of contexts (e.g., stereotypes, political beliefs, financial decisions, beliefs in psychic abilities), and serves to strengthen current beliefs. Furthermore, the confirmation bias generates additional collateral “evidence,” allowing beliefs to persist even when the initial evidence is discredited, because we can draw on evidence obtained from a variety of sources. As a quick test of the confirmation bias, readers can look through their personal collections of books. Do you have an equal number of books that are both consistent and inconsistent with your beliefs? Do you subscribe to or read periodicals, newspapers, etc. that present perspectives contrary to your political beliefs? (The authors confess that their book collections and periodical and newspaper subscriptions are highly skewed in favor of their political beliefs.) Likewise, how do you feel about opposing political perspectives, especially concerning issues you are keenly interested in (e.g., the current Iraq war, school vouchers, privatization of Social Security accounts)? Do your feelings influence your assessment of the correctness of different perspectives? Likewise, are you surrounded primarily by others that share your views, which in turn strengthens your beliefs (i.e., group polarization)? A consistent skeptic would not be biased toward confirmatory evidence.
Second, we are biased in assimilating information into our belief systems. Not only do we seek out information that supports our beliefs, but we also apply differing standards of evidence. As research has demonstrated, “People who hold strong opinions on complex social issues are likely to examine relevant empirical evidence in a biased manner. They are apt to accept ‘confirming’ evidence at face value while subjecting ‘disconfirming’ evidence to critical evaluation, and as a result to draw undue support for their initial positions from mixed or random empirical findings” (Lord, Ross, and Lepper 1979, p. 2098). A consistent skeptic would apply the methods of skepticism to all claims consistently and evaluate the evidence in an unbiased manner (i.e., without double standards).
Finally, many studies have demonstrated that it can be difficult to change a belief even when substantial discrediting information is provided (i.e., belief perseverance; see Anderson and Kellam 1992). This is especially true when we have constructed a rationale supporting the belief, or for strongly held emotional beliefs (Edwards 1990). Belief perseverance explains why a “true believer” (e.g., Sir Arthur Conan Doyle, who believed that mediums could communicate with spirits) continues to maintain beliefs despite powerful discrediting evidence (e.g., Harry Houdini’s exposure of mediums as frauds or confessions by the mediums). Furthermore, research by Tetlock (1998, 1999) has shown that experts also go to great lengths to maintain belief systems, even in the face of strong evidence that should force them to reconsider viewpoints. A consistent skeptic should obviously use discrediting information to modify beliefs.
Not only do we lack the time and universal expertise to be consistent skeptics, but our minds have a variety of built-in biases that directly hinder nonselective skepticism. These biases are especially powerful in defending long-held beliefs in which we have a strong emotional investment. Even the most ardent skeptic does not like to have his or her most cherished beliefs subjected to rigorous skeptical inquiry.
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