Appeal to Personal Incredulity
Tuomas W. Manninen
I fail to understand how teachers can call themselves Christians, go to church, talk about God, talk about Christ, and then go to school five days a week and talk about Darwin, and teach it as if it’s fact, not a theory, but that’s how it happened.
I don’t understand it. To me that’s talking out of both sides of your mouth.Bill Buckingham, in Judgment Day: Intelligent Design on Trial
The fallacy of appeal to personal incredulity is committed when the arguer presumes that whatever is true must be easy to understand or to imagine. Hence, if something is easy to understand or to conceive, it must be true; conversely, if it is difficult (or impossible) to understand, then it is false (Baggini 2009; Bebbington 2011). This line of reasoning seems to undercut the fact that we rely on expert opinions in many (if not most) parts of our lives. After all, we visit doctors when we seek an explanation for something that ails us. Likewise, we seek expert opinions in innumerable other facets. The fallacy seems to be most frequent when the contrasting expert opinions differ from our deeply held beliefs. As a result, we try to discount the expert view by appealing to the perceived difficulty in understanding it.
The fallacy is very commonly found in debates over science. In the Judgment Day documentary, Bill Buckingham is incredulous of how someone can both claim to be a Christian and teach science - especially Darwin’s theory of evolution (NOVA 2007). In Darwin’s Black Box, its author
Dr. Michael Behe cannot see how natural selection could produce biological systems that appear to be irreducibly complex (cited in Bebbington 2011 and in NOVA 2007). But the fallacy becomes clear when we take a step back from these claims. Just because Mr. Buckingham cannot imagine how someone can be a scientist and profess Christian faith does not mean that these two viewpoints cannot be reconciled.
Similarly, because the fact that Dr. Behe cannot see how natural selection could produce irreducibly complex biological systems may be more of an indictment of Dr. Behe’s understanding of natural selection, and less of the fact that natural selection can produce seemingly irreducible complex systems. To be fair, Dr. Behe does qualify his statement on irreducibly complex systems by adding if there is such a thing” (cited in Bebbington 2011, 28).In a variant of the fallacy, a person may to appeal to her lack of understanding on a subject matter in a seemingly more self-deprecating manner as a backhanded way of undermining expert authority. This has been a recent talking point for many American politicians, as a number of them have responded to questions on whether they accept the scientific consensus on anthropogenic climate change. As if read from a common script, the politician has acknowledged “I am not a scientist,” only to proceed to discuss the negative impact of policies based on the scientific consensus (Chait 2014). The general pattern of the fallacy in these cases (roughly) follows these steps:
Step 1: Politician X is asked whether or not s/he accepts the scientific consensus on topic Y.
Step 2: X acknowledges that s/he doesn’t understand Y, because s/he is not a scientist; X defers any such question to the experts.
Step 3: X goes on to promote her/his own initiative on Y on the grounds of economy.
Curiously, Step 3 is offered without any qualifications on X’s expertize on economics.
The steps to avoid committing the appeal to personal incredulity fallacy are rather straightforward. However, this is not to say that these steps are easily taken. When faced with a claim that one does not understand, the epistemically responsible thing to do would be to seek to expand one’s understanding. However, when the claim in question challenges one’s ideology - or any other belief one holds near and dear - one can become extremely reluctant to entertain such a challenge with an open mind. The same considerations apply, and the same difficulties are present, whether we deal with our own case or that of our opponent in an argument. Ultimately, it seems to come down to the level of obstinacy, either in ourselves or in our opponent.
References
Baggini, Julian. 2009. The Duck that Won the Lottery. London: Penguin Books. Bebbington, Dene. 2011. Think 10(28): 27-28.
Chait, Jonathan. 2014. “Why Do Republicans Always Say ‘I’m Not a Scientist’?” New York Times Magazine, May 30. http://nymag.com/daily/intelligencer/2014/05/why- republicans-always-say-im-not-a-scientist.html (accessed September 25, 2017).
NOVA. 2007. Judgment Day: Intelligent Design on Trial. PBS, November 13. http:// www.pbs.org/wgbh/nova/evolution/intelligent-design-trial.html (accessed September 25, 2017).