Children’s quantification of time with the comparative “more”

Events can be quantified along several dimensions— E.g., walking can be measured by number of steps taken, distance traveled, or time spent walking. In quantifying events with the comparative “more” (e.g., “Who did more walking?”), one must first identify the relevant dimension of quantification and encode each magnitude, before projecting them onto a common scale of degrees to support linguistic comparison. In the current study, we asked whether young children are able to do so for duration, which may be less salient than number or space. While previous work has established that children quantify number and space with “more” by 3 ½ years old, it is unknown whether children are able to quantify duration around this age, or whether this ability emerges later in development, perhaps closer to when children learn duration words such as “minute” and “hour” around 6 or 7 years old. In three studies, we asked children to identify who did “more” of an action (e.g., stretching) performed by two actors for varying durations. We found that children could quantify duration with “more” by 3 or 4 years old. These results suggest that children can identify time as the relevant dimension of quantification and encode a comparison of the magnitude of durations linguistically years before mastering duration words, and around when they become able to quantify magnitudes in more concrete domains such as number and space.