11.2 The distinct functions of belief and opinion THE CONFUSION BETWEEN BELIEF AND OPINION AND THE NATURES OF FANATICISM AND PHILISTINISM. PART 3.

Belief, relying on the opinions of epistemic superiors and equals, is the rational basis for controlling outcome, but effective deliberators must express their opinions, as in the 1957 movie "Twelve Angry Men." A single holdout—without claim to epistemic superiority—stood firm and averted an innocent defendant's conviction. In rational-belief formation, agents discount their own opinions following their overwhelming rejection by epistemic equals. For rational belief, the dissenter should assign no greater weight to his own opinion than to other jurors'; but had he based his position on rational belief, the jury would have convicted wrongly. Under the (false) assumption that deliberation is based on belief, the independent juror would have been irrational in his stubborn defense of personal opinion. That's wrong: jurors are supposed to be independent. Jury instructions, though not philosophically explicit, imply that jurors should form independent opinions, influenced only by other jurors' arguments, not the belief-constituting average opinion of epistemic equals. The other eleven jurors, who decidedly were not paragons of rationality, adopted group-average opinion to form, irrationally, a bloc against the dissenter.

Opinions and beliefs serve separate valid roles. Whereas belief is the rational basis for outcome control, opinion is the substantial basis for deliberation, which contests opinions to adjust belief. Deliberation flourishes when independent contributions foster the debate driving it.

Scientific and philosophical debates resemble jury deliberations. Although rational belief is a weighted average of all the experts' beliefs, to reach beliefs least prone to error each scientist involved must first serve as an independent "measuring instrument," only later submitting to an ultimate computation of a group average. Philosophers' attitudes are typified by Hume's when he skeptically rejected causality, opining that no future expectancies are justified, and causality is mere habitual association. Yet, he admittedly disregarded his philosophical conclusions in practical matters. Hypocrisy? No, Hume was properly distinguishing his belief that causality is objective from his opinion that it's illusion. Hume advanced philosophy by cultivating his independent opinion, which, like all good philosophers, he tried to conform to his reasoning, but he disbelieved his skepticism.

Philosophers and scientists distinguish the research program they pursue from the tenets they believe, but political disagreement is different. In an election-based system expressing deeply opposed interests, political advocacy simultaneously serves deliberative and outcome-controlling functions, because democratic debate serves to both answer and decide political questions. Democratic debate is premised on deliberation, while democratic process is premised on outcome control, and when a single venue simultaneously serves both functions, the deliberative function suffers. If the other jurors continued stating beliefs rather than forming opinions, the dissenting juror's deliberative efforts would have been futile, but outcome control is more robust. Whereas deliberation is stymied when some jurors substitute the drive to control the outcome for the desire to find the truth, outcome control is facilitated when others distractedly pursue other goals.

While beliefs rather than opinions guide political debate, when their deliberation is obstructed the intended beliefs never progress beyond opinion. The pathologies of belief and opinion, the subject of the next essay, derive from this political concoction and its thorough confusion of belief and opinion.

Next posting: Pathologies of belief-opinion confusion.