The DSM-III symptomatic criteria for major depression (MD) were derived from those proposed by Feighner and colleagues in 1972, which closely resembled those published by Cassidy in 1957. I here present a counter-factual history in which Feighner carefully read a key reference in Cassidy, a large 1953 follow-up study by Campbell of depressed patients with detailed tables of depressive signs and symptoms. In this alternative timeline, the Feighner criteria for MD were modified by Campbell's results, which then changed DSM-III and subsequent MD criteria sets. The historical pathway to the current DSM MD criteria was contingent on a range of historical events and could easily have been different. This story is not meant to criticize DSM MD criteria that perform well. Rather, it suggests that these criteria represent a useful but fallible set of symptoms/signs that index but do not constitute MD and therefore are not to be reified.