Use, truth and time constitute the basic elements of the epistemological structure of history. That structure went through three stages: pre-modern (from ancient times to the late eighteenth century, before the professionalization of history took place), modern (the period of professional history, from the late eighteenth century to the 1970s), and post modern (post 1970s). In these three stages, use, truth, and time successively occupied the core of the epistemological structure of history. Postmodernist history, which puts time at the core of its epistemology, is an extreme form of historicism. Even more than historicism, it has emphasized the determining effect of time and change on historical truth and historical consciousness. The privatization of historical narrative and reading has prodded history to become experimental. Experimental history no longer proclaims the truth about the past. Instead, under specific historical circumstances, it strives to produce texts that will be recognized by individual historians and provides these texts to readers, who will make their own judgments. Whether these texts are true will be decided through the uses they produce. In this way, any historiographical practice will be an experiment conducted by an historian in the present and that will consist in searching for the truth about the past. The success of this experiment will depend entirely on the experimental environment, that is, on the conditions provided by the reading environment.