While some biases are less prevalent among those who score high on standard measures of academic intelligence, others appear to be no less frequent or powerful. Stanovich, West and Toplak (2013), reviewing several studies, find that the degree of myside bias is largely independent of measures of intelligence and cognitive ability. Dan Kahan finds that on several measures people who use more “System 2” type explicit reasoning show higher rates of motivated cognition rather than lower rates (2011, 2013, Kahan et al 2011). Thinkers who are more knowledgeable have more facts to choose from when constructing a line of motivated reasoning (Taber and Lodge 2006; Braman 2009).
Nor does disciplinary expertise appear to be protective. For instance, Schwitzgebel and Cushman (2012, 2015) presented moral dilemma scenarios to professional philosophers and comparison groups of non-philosophers, followed by the opportunity to endorse or reject various moral principles. Professional philosophers were just as prone to irrational order effects and framing effects as were the other groups, and were also at least as likely to “rationalize” their manipulated scenario judgments by appealing to principles post-hoc in a way that would render those manipulated judgments rational.
Furthermore, since the mechanisms responsible for rationalization are largely non-conscious, vigilant introspection is not liable to reveal to the introspector that rationalization has occured. This may be one reason for the “bias blind spot”: People tend to regard themselves as less biased than others, sometimes even exhibiting more bias by objective measures the less biased they believe themselves to be (Pronin, Gilovich and Ross 2004; Uhlmann and Cohen 2005). Indeed, efforts to reduce bias and be vigilant can amplify bias. You examine your reasoning for bias, find no bias because of your bias blind spot, and then inflate your confidence that your reasoning is not biased: “I really am being completely objective and reasonable!” (as suggested in Erhlinger, Gilovich and Ross 2005). People with high estimates of their objectivity might also be less likely to take protective measures against bias (Scopeletti et al 2015).
Many judgments admit of degrees, and motives can have impacts of small degree. They can affect the likelihood you assign to an outcome, or the confidence you place in a belief, or the reliability you attribute to a source of information, or the threshold for cognitive action (e.g., what would trigger your pursuit of an objection). They can affect these things in large or very small ways.
Such micro-instances (you might call it motivated reasoning lite) can have significant amplificatory effects. This can happen over time, in a linear fashion. Or it can happen synchronically, spread over lots of assumptions, presuppositions, and dispositions. Or both. If introspection doesn't reveal motivated reasoning that happens in one fell swoop, micro-instances are liable to be even more elusive.
Coming next week: Why Moral and Philosophical Disagreements Are Especially Fertile Grounds for Rationalization.