The Surprisingness of Coincidences1

Abstract Coincidence-type stories, a popular social pastime, were studied in terms of factors affecting their surprisingness. Subjects were presented with stories varying in tense (past vs. future) and scope of detail (union vs. intersection). The normal form of coincidence stories, past-intersection, was found to be judged less surprising than stories of identical scope told in the future tense and similar in surprisingness to past-tense stories of greater scope. Subjects judged their own coincidences as more surprising than coincidences constructed by the experimenters and more surprising than when evaluated by a separate group of subjects. Implications of these results are discussed in terms of what we may remember or learn from experiences related by others.