David S. Nivison, well known for his wide-ranging studies of Chinese history and philosophy, was the Walter Y. Evans-Wentz Professor Emeritus at Stanford University. Before he passed away on October 16, 2014, he sent the following two essays to BJAS. Though conceived separately, the relationship between the two essays is self-apparent, and the editors have chosen to present them together in this issue. Both essays attempt to take seriously the knowledge of Warring States scholars with regard to Chinese chronology as ancient as the beginning of the second millennium B.C. The first essay is entitled “Was Warring States China ahead of Greece in Science? ” Using both the Bamboo Annals and other early sources, Nivison argues that the compilers of the Bamboo Annals had astronomical records from the remote past that were far superior to those of the ancient Greeks. He thus answers his own question in the affirmative with regard to this particular issue. The second, “The 31 Years Problem, ” presents an intricate argument regarding a single discrepancy in the chronology of the Bamboo Annals, which Nivison argued was an authentic and largely accurate chronology. The essay includes thought-provoking reflections on epistemology and the philosophy of history. Nivison's unique combination of historical breadth and rigorous numbercrunching leads to countless keen observations, and challenges us to treat ancient texts seriously and with imaginative sympathy. The two essays are presented here with only slight editing, since their informal writing style vividly captures Nivison's creative thought processes.