A disconfirming strategy is not necessarily better than a confirming strategy

College students were presented with 4 events to be explained. Each event was accompanied by either a target explanation or a target and an alternative, and all explanations were causal mechanistic. For each event, participants were also presented with 12 pieces of information. Four of the 12 pieces were causally consistent with the target, 4 with the alternative, and 4 were neutral. Participants were assigned to one of 3 strategy conditions, depending on what they were explicitly told to do: confirm, disconfirm, or evaluate the target explanation. People told to disconfirm were more likely than people in the other conditions to cite, as strategy appropriate, information that was in fact neutral. In addition, across strategy conditions, the presence of an alternative decreased the likelihood of identifying, as appropriate to the strategy, information that was strategy inappropriate. Results are discussed in terms of inference to the best explanation and in terms of confirmation bias.