The employees of a company are trying to decide whether to give up a pay raise so they can afford to install a workplace safety measure. Each employee will vote for the sacrifice if she thinks the danger is sufficiently serious, if the safety measure is sufficiently effective, and if the pay sacrifice is sufficiently bearable. Otherwise she’ll vote against it. The three employees come to this result:
This is troubling: A majority of employees supports each of the criteria, and yet each of the three resolves to reject the proposal. If the employees reach their decision by comparing their views about the measure as a whole, then they’ll reject the pay sacrifice. But if they compare their views about each criterion, they’ll accept it.
Princeton philosopher Philip Pettit worries that this phenomenon makes it impossible for us to make confident statements about the beliefs of a group. “Going the conclusion-driven way means adopting a course that is inconsistent with the premises endorsed by the group, and going the premise-driven way means adopting a course that a majority individually reject.”
Both outcomes are undesirable. “Going the first way means sacrificing collective rationality for the sake of responsiveness to individuals, going the second means sacrificing responsiveness to individuals for the sake of collective rationality.”
(Philip Pettit, “Deliberative Democracy and the Discursive Dilemma,” Philosophical Issues 11:1 , 268-299.)