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Figure 2: Energy rate density, Φm, for a wide spectrum of systems observed throughout Nature displays a clear increase across ~14 billion years, implying rising complexity throughout all known historical time. The solid blue curve in this “master plot,” graphed on the same temporal scale as in Figure 1, implies an exponential rise as cultural evolution (steepest slope at upper right) acts faster than biological evolution (moderate slope in middle part of curve), which in turn surpasses physical evolution (smallest slope at lower left). The shaded area includes a huge ensemble of Φm values as many different individual types of complex systems continued changing and complexifying since their origin; the several small dashed blue lines within that shaded area delineate some major evolutionary events that are then graphed in greater detail in Figures 39. The Φm values and historical dates plotted here are estimates for specific systems on the evolutionary path that led to humankind, namely, the Galaxy, Sun, and Earth, as well as much life all across our planet. As such, this particular graph is of the greatest relevance to big historians seeking to understand how human society emerged naturally over the course of all time.