Improbable but Possible: Training Children to Accept the Possibility of Unusual Events

Young children tend to deny the possibility of events that violate their expectations, including events that are merely improbable, like making onion-flavored ice cream or owning a crocodile as a pet. Could this tendency be countered by teaching children more valid strategies for judging possibility? We explored this question by training children aged 4-12 (n = 128) to consider either the similarity between the target event and unusual events that have actually occurred or causal mechanisms that might bring the target event about. Both trainings increased children's acceptance of improbable events but only for the types of events addressed during training. Older children were more likely to accept improbable events, as were children who scored higher on a measure of cognitive reflection, but neither age nor cognitive reflection moderated the effects of training. These findings indicate that children can use both similarity and causality to assess possibility, but the use of this information is highly circumscribed, further demonstrating how robustly children conflate improbability with impossibility. Public Significance Statement Children tend to claim that unusual events are impossible, and this study explored the source of that tendency by training them to consider real events similar to the target events or mechanisms that cause the target events to occur. We find that both types of information increase children's acceptance of unusual events but only for events similar to those covered during training, which suggests that children appreciate the kinds of considerations relevant to possibility but do not seek out those considerations on their own.