This study examined the interaction between reasoning strategies, such as gathering evidence to develop an argument, and subject-specific knowledge. Two groups participated in this study which was divided into two parts. The first group was fifteen final year history undergraduate students at an American university and the second group was fifteen American specialists in modern history.

In the first part participants answered a questionnaire related to their previous knowledge about the Moriscos’ expulsion from Spain in 1609. Each participant was also interviewed to examine their hypothesis about the reason for the expulsion. In the second part the participants were first given a short text where they were presented with a historical problem they had to solve. Specifically, they were asked to answer the question: “To whose advantage was the expulsion of the Moriscos in the Duchy of Gandía?” Then they were provided with five more documents with more information about the problem and asked to re-answer the question. Lastly, each participant was presented with a table containing data which conflicted with the second answer they had given and their hypothesis about the reasons for the expulsion was once again evaluated.

Only half of the participants changed their hypothesis in this last section of part two. Overall, the undergraduate students were more likely to change their hypothesis than the history specialists.