ABSTRACT

In this chapter, the author summarizes his understanding of the experimental data and their interpretation in the Piagetian literature regarding the quantification of inclusion relations. The experiments were carried out with 60 5-year-old Amsterdam kindergarten pupils from a part of the city were families lived from lower to middle socioeconomic strata. The children were divided into three groups of 20. The first group (Group I) learned to deal with quantifying the inclusion relations in only verbally presented classes and subclasses. The second group of children learned to quantify the inclusion relations of classes and subclasses by showing them 10 pictures of flowers, animals, people and vehicles. The children were divided into three sub-groups: "success," "partial success," and "no success". For the third group little Lego bricks—very familiar to Dutch children—of various colors and sizes were used.