“Soft” Versus “Hard” Psychological Science: Biased Evaluations of Scientific Evidence That Threatens or Supports a Strongly Held Political Identity

Abstract

Perceptions of the quality of two kinds of psychological methods—brain magnetic resonance imaging (MRI) and cognitive testing—were assessed in response to a scenario in which an expert's opinion rendered a politician incompetent to continue in his elected position. Participants evaluated the quality of MRI evidence more favorably than cognitive testing evidence, an effect that was particularly pronounced among participants motivated to disbelieve the evidence (strong partisans of the same party as the politician). This study is among the first to underscore the potential real-world implications of layperson's perceptions of psychological methods and to highlight that evaluations of “softer” methods may be more malleable than the “harder” ones.