Single-Heuristic Reasoning: Is It Still Dual-Process?

Traditionally, paradigms used to study conflict in reasoning (and metacognition during reasoning) pit heuristic processes against analytical processes. Findings indicate that the presence of conflict between processes prolongs reasoning and decreases accuracy and confidence. In this study, we aimed to explore reasoning and metacognition when only one type of heuristic process is exploited to cue multiple responses. In two experiments, a novel modification of the Base Rate neglect task was used to create versions in which one belief-based heuristic competes, or works in concert, with another of the same type to provide a response. Experiment 1 results reveal that the presence of conflict between cued responses does not affect meta-reasoning, which indicates that reasoning defaulted to a single process. An alternative explanation was that the effect of conflict was masked due to an imbalance in the strength of the dominant response between conflicting and congruent versions. Experiment 2 was designed to test hypotheses based on these competing explanations. Findings show that when the strength of a response was no longer masking the effect, the conflict did result in longer reasoning times and lower confidence. The study provides more robust evidence in favor of the dual-process account of reasoning, introduces a new methodological approach, and discusses how conflict may be modulated during reasoning.