Glick (1975). Cognitive development in cross-cultural perspective.

“For example, in the sorting task, twenty items representing five types of food, five types of clothing, and five types of cooking utensils were heaped on a table in front of a Kpelle subject. When the subject had finished sorting, what was present were ten categories composed of two items each — related to each other in a functional, not categorical, manner. Thus, a knife might have been placed with an orange, a potato with a hoe, and so on. When asked, the subject would rationalize the choice with such comments as, ‘The knife goes with the orange because it cuts it.'”

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