Chapter 13: History and Science after the Chronometric Revolution

This paper describes a transformation in our understanding of the past, a transformation whose full significance has not yet been adequately appreciated. The transformation is associated with a revolution in the techniques used to date past events. I will argue that this "chronometric revolution," which occurred in the middle of the 20th century, has large implications for our understanding of both history, and of the relationship between history and science.

The first part of this essay reviews the changing relationship between history and the sciences in the western world over several centuries. The second part describes the "chronometric revolution." The discipline of history has been transformed by two great chronometric revolutions. One occurred several millennia ago, after the appearance of writing. Written records made it possible, for the first time, to assign absolute dates to events many generations in the past. The second revolution occurred soon after the Second World War. It allowed us to assign reliable absolute dates to events extending back to the very origins of the universe. The third part explores some of the consequences of the chronometric revolution. By expanding our vision of the past to eras well before the appearance of our own species, the chronometric revolution historicized disciplines such as cosmology, geology, and biology and brought them closer in their methodologies to the discipline of history. The fourth part argues that the idea of increasing complexity offers a powerful thematic link between this newly discovered cluster of historically oriented disciplines. Over 13 billion years, increasingly complex entities have appeared in the universe, and modern human society may be one of the most complex of all these entities. Finally, the expanded vision of the past made possible by the chronometric revolution raises important questions about the distinctive nature of human history. I will argue that our species is distinguished by two complementary "emergent" properties. The first is an exceptional ability to adapt to different environments. The second is a unique capacity for seeking and finding "meaning." As a species we have a quite exceptional ability to keep finding new ways of adapting to our environments. I will argue that the source of this ability is "collective learning" -- the ability, unique to our species, to share learned information with precision and in great volume. That ability in turn is linked to our propensity for finding "meaning" through the sharing of symbols. In the light of these arguments, I will suggest that the expanded past revealed by the chronometric revolution allows us to redefine our sense of the past in general and of human history in particular.