Pretend play is a common childhood activity, in which a pretender’s mental representation is intentionally and with full awareness projected onto reality in a spirit of play or fun. For example, one might gallop around with a stick, projecting one’s representation of a horse onto the stick, or one might have tea with an imaginary companion, projecting a full person onto an empty space. Such behaviors are present in every culture and on a set time schedule, leading to the supposition that the behavior itself has been selected for, in the evolutionary sense. Alternatively, pretend play might be a byproduct of another ability, specifically symbolic representation. Although the pioneering developmental psychologist Jean Piaget claimed that pretend play largely disappears around age 6, more recent research ...