This chapter engages critically with Carol Cleland's recent work in the philosophy of historical science. Much of the practice of historical geology fits her description of the methodology of “prototypical historical science” quite well. However, there are also important kinds of historical scientific research that do not involve what she calls the search for the smoking gun. Moreover, Cleland's claim that prediction is not a major factor in historical natural science depends on taking an overly restrictive view of what counts as a prediction. Finally, Cleland's approach, which emphasizes methodology, is just one possible way of thinking about the difference between historical and nonhistorical science. Rather than focusing on the “how” of historical science, one can also focus on the “what” of historical science—on the nature of the processes and events that historical geologists study.