Unless conditionals: New evidence from priming

Abstract

Using a priming paradigm, the possibilities that people keep in mind in order to understand “unless A, B” were compared to those from “if A, not-B” conditionals. The length of time it took people to read conjunctions as “A and B”, “A and not-B”, “not-A and B”, and “not-A and not-B” after they had been primed by the different conditionals was measured. The results show that, whereas people rely on one possibility to understand “if”, they rely on two possibilities to understand “unless” conditionals. Results are discussed within the mental models framework.

Keywords:

• Mental models
• Reasoning
• Unless conditionals

Acknowledgments

This research was supported by Grants PSI2008-00754/PSIC and PSI2011-29504 from the Spanish Ministry for Science and Innovation.