Coincidences: A fundamental consequence of rational cognition

Abstract

Believers tend to view the experience of coincidences as evidence for a variety of paranormal beliefs in mind and mysterious causal mechanisms out in the world. On the other hand, skeptics (e.g. most psychologists) tend to dismiss the psychological experience of coincidences as just yet one more demonstration of how irrational people can be. Irrationality in this context means an association between the experience of coincidences and biased cognition in terms of poor probabilistic reasoning and a propensity for paranormal beliefs. In this article, we present a third way: the rationalist perspective on the psychology of coincidence occurrence. We develop this new emphasis, including a new definition of coincidence, out of reviewing and synthesizing the extant literature on coincidences. We then propose a new three stage model to describe the psychological experience of coincidence, the 3C's model: 1. (C)o-incidence detection, 2. (C)ausal mechanism search 3. (C)oincidence versus cause judgment. The core principles in this model are that people use the same properties relevant for causal reasoning when detecting and evaluating events that are ultimately judged to be coincidental, and we describe how the model can account for the key prior research on coincidences. Crucially, rather than just being examples of irrationality, we argue that the experience of coincidences is a necessary consequence of rational causal learning mechanisms and provides a widely ignored approach to evaluating the mechanisms of causal reasoning.