Developmental change in early representational intelligence: Evidence from spatial classification strategies and related verbal expressions

The procedures 1- to 3-year-old children use to group simple sets of objects are analyzed in an investigation of cognitive change in early representational intelligence. Forty children spontaneously manipulated two-class arrays and participated in two experimental probes of object grouping. Children 1 to 2 years of age group classes by looking for one kind of thing at a time. Consistent with this, they verbally mark single classes. Children from $\text{2}\text{1}\text{2}$ to 3 years old employ spatial grouping procedures that require simultaneous consideration of two classes, and they refer to relations between classes. Advances made during the second year are consistent with other initial signs of representational-symbolic intelligence. The advances in the third year are unaccounted for by traditional cognitive-developmental theories, but they are congruent with late-emerging patterns in natural representational systems such as language, suggesting the presence of broad changes in mental organization shortly after the onset of representational intelligence.