This original work caps years of thought by Leonard Krieger about the crisis of the discipline of history. His mission is to restore history's autonomy while attacking the sources of its erosion in various "new histories," which borrow their principles and methods from disciplines outside of history. Krieger justifies the discipline through an analysis of the foundations on which various generations of historians have tried to establish the coherence of their subject matter and of the convergence of historical patterns. The heart of Krieger's narrative is an insightful analysis of theories of history from the classical period to the present, with a principal focus on the modern period. Krieger's exposition covers such figures as Ranke, Hegel, Comte, Marx, Acton, Troeltsch, Spengler, Braudel, and Foucault, among others, and his discussion involves him in subtle distinctions among terms such as historism, historicism, and historicity. He points to the impact on history of academic political radicalism and its results: the new social history. Krieger argues for the autonomy of historical principles and methods while tracing the importation in the modern period of external principles for historical coherence. Time's Reasons is a profound attempt to rejuvenate and restore integrity to the discipline of history by one of the leading masters of nineteenth- and twentieth-century historiography. As such, it will be required reading for all historiographers and intellectual historians of the modern period.