Disagreement, Dogmatism, and Belief Polarization

Consider the phenomenon of belief polarization. Suppose that two individuals—let’s call them ‘You’ and ‘I’--disagree about some non-straightforward matter of fact: say, about whether capital punishment tends to have a deterrent effect on the commission of murder. Although neither of us is certain of his or her view, I believe that capital punishment is a deterrent while You believe that it is not. Perhaps one or both of us has evidence for his or her view. Or perhaps we hold our views on the basis of ideological dogma, or on the basis of some admixture of dogma and evidence. In any case, regardless of why we believe as we do, You and I disagree, in a perfectly familiar way. Suppose next that the two of us are subsequently exposed to a relatively substantial body of evidence that bears on the disputed question: for example, statistical studies comparing the murder rates for adjacent states with and without the death penalty. The evidence is of a mixed character: some studies seem to suggest that capital punishment is a deterrent while other studies seem to suggest that it is not. Regardless, the entire body