A review of the idea of zero and its forerunners in childhood
Giulia Vigna, Silvia Benavides-Varela
Studies on the numerical development of zero are scarce. However, given its long historical development and its distinctive characteristics, paying particular attention to it is warranted. This article summarises the main studies that have analysed how this concept and its precursors develop in young children. Initially, it was thought that children could not handle zero before 6 years of age. Today, instead, we know that pre-schoolers are able to represent the empty sets on the same numerical continuum as non-empty sets and that even some animal species can do it. In addition, younger children are able to manipulate empty sets in order to complete numerical tasks, in spite of the fact that they are not always aware that zero is a number. Finally, recent research has underlined that the understanding of zero is independent from the understanding of the cardinality of small numbers. Zero is probably a complex idea, which develops over time from certain basic abilities that humans share with some animals.
Keywords
Zero, Empty sets, Numerical cognition, Pre-school, Animal cognition.