Where the truth lies: how sampling implications drive deception without lying


Efficient communication leaves gaps between message and meaning. Interlocutors, by reasoning about how each other reasons, can help to fill these gaps. To the extent that such meta-inference is not calibrated, communication is impaired, raising the possibility of manipulation for deceptive ends. We examined how people reason when acting as the perpetrator or target of deception across two related experiments. Importantly, the nature of the task precluded outright lying. Thus, deception required withholding information or providing data that was factually correct but nonetheless misleading. We find evidence for two distinct patterns of behaviour. One group of people appear to make assumptions about communicative intent based on context and message content. Senders in this group were more likely to mislead, and receivers were more effectively misled. A second group of people appeared to adopt a more defensive stance, displaying the same cautious approach in all situations. We explain this behaviour using a computational account of the kinds of inferences required by both receiver and sender. These distinct patterns arise from different assumptions about the generative process behind communication.

Preprint submitted for publication