Most historians let collective memories guide their work, with what needs to be studied already understood to matter. This is particularly true for histories of the recent past, in which primary-source research serves, to quote Michel Foucault, “to refresh memory.” Memorial histories are of different types—including nationalist histories, militant histories, and family or group histories—and useful. There are other approaches to studying the past, however, that can help even those committed to memorial practices. This article draws from work by Bonnie G. Smith, Laura Doan, and Foucault to home in on two key historical practices: “primary-source work” and “historiography.” A sharper awareness of what these practices are, their possibilities, and, of pressing importance, their limits—what they cannot or tend not to reveal, what they in fact render more difficult to see—could help make debates about presentism more convincing. The article proposes “prospecting” as a way to identify research topics that might stimulate present-day discussions and also engage other scholars.