One, Two, Three, Four… What's More? Successor Relations, not Mappings to Approximate Magnitudes, Support Learning the Later-Greater Principle.

As we count up, number words that occur later in our count denote greater quantities. Here, we tested whether children's understanding of this "later-greater" principle originates from associating number words with approximate magnitudes, or if instead it arises from knowledge of successor relations between individual number words. In Experiment 1 (N = 60), we found that children can identify the greater of two small number words (e.g., "six" vs. "ten") based on associative mappings between number words and the ANS but do not rely on such mappings to compare larger numbers (e.g., "twenty-four" vs. "twenty-six"). In Experiment 2 (N = 60), we replicate these findings and show that children's knowledge of successor relations between number words predicts later-greater knowledge, while mappings to the ANS do not. We conclude that children's knowledge of successor relations, but not associative mappings to approximate magnitudes, are implicated in learning the later-greater principle.