The Deeper Themes of Arrows and Cycles

I have lectured for years in my introductory courses about the themes of time's arrow and time's cycle. Often, a student will ask, with that charming naiveté of a freshman who thinks that professors really do have simple answers to the deepest questions of the ages: Well, which is right? I always reply that the only possible answer can be "both and neither."

We often try to cram our complex world into the confines of what human reason can grasp, by collapsing the hyperspace of true conceptual complexity into a single line, and then labeling the ends of the line with names construed as polar opposites—so that all richness reduces to a single dimension and contrast of supposed opposites. All these dichotomies are false (or incomplete) because they can capture but a fraction of actual diversity, but one might be better (or at least more productive) than another because the limited axis of its particular contrast might express something more fundamental, more extensive in implication, or more in harmony with concerns of the actual debaters (see Chapter 1 for a fuller discussion of dichotomy).

I concluded that, if we must dichotomize, time's arrow and time's cycle is the most fruitful contrast for understanding the major issues underlying the greatest transformation that geology has or could contribute to human thought—the discovery of deep time. I reached this conclusion for several reasons: I believe that the major actors who struggled with time and the meaning of history from the late seventeenth through the mid-nineteenth century kept such a dichotomy at the forefront of their thought; thus, although arrow versus cycle may be as restrictively simplified as any single contrast, it was, at least, their dichotomy. For me, this contrast became a key for unlocking both the structure and meaning of great historical documents that I had read several times before, but had never understood or grasped as unified statements. But I also regard arrow versus cycle as a particularly "good" dichotomy because each of its poles captures a deep principle that human understanding of com-