Steps, stages, and structure: finding compensatory order in scientific theories.

Stage theories are prominent and controversial in science. One possible reason for their appeal is that they provide order and predictability. Participants in Experiment 1 rated stage theories as more orderly and predictable (but less credible) than continuum theories. In Experiments 2-5, we showed that order threats increase the appeal of stage theories of grief (Experiment 2) and moral development (Experiments 4 and 5). Experiment 3 yielded similar results for a stage theory on Alzheimer's disease characterized by predictable decline, suggesting that preference for stage theories is independent of valence. Experiment 4 showed that the effect of threat on theory preference was mediated by the motivated perception of order, and Experiment 5 revealed that it is particularly the fixed order of stages that increases their appeal.