Abstract: Research on children’s understanding of illness is particularly concerned from the perspective of conceptual change and cognitive development. Instead of focusing on general logical structures as Piaget did, recent idea of conceptual change presupposes the domain-specificity of cognitive development. There is still debate on whether young children acquired a separate biological domain and how that domain can best be characterized. This research was designed according to the 3 components of naïve biology to shed light on the above issue. Study 1 investigated whether preschool children regarded illness as a biological process to distinguish living and nonliving things. Study 2 further investigated their understanding of non-intentionality of the cause and prevention of illness. Study 3 explored how children explained the causes of illness spontaneously and compared their responses with adults.
The sample in the 3 studies comprised the same group of 90 preschoolers, with 30 children in each of the following age groups: 3-, 4- and 5-year-olds, with equal numbers of boys and girls. Participants were recruited from different SES families in Beijing, China. Study 3 also recruited 30 college students as a comparison of adult group. In study 1, a classification task was used. Children were requested to classify sets of living and non-living things in terms of illness. In study 2, several stories were told to children, asking them to tell whether some specific behavior might cause or stop illness. Study 3 was an interview task, asking children and adults to offer their own explanation of the cause of illness. Participants responses were coded into one of the 5 coding categories: Psychogenic, Biological, Behavioral, Symptomatic and others.
Results indicated that preschoolers’ performance increased with age in the classification task, they understood better that living things could get sick, while non-living thing couldn’t when getting older; Even 3-year-olds realized that illness was non-intentional, intention could neither cause illness nor stop illness; Children neither used intention nor moral rules to explain illness but from behavioral perspective most frequently. This may support that they had separated theory of naïve biology.. However, their explanations were different from adults’ level and scientific biological concept, since adults offered more biological and psychogenic explanations. The studies also found educational background influenced children’s illness understanding, while high SES children outperformed their low SES counterparts in all the 3 studies, implying family and preschool education may enhance children’s cognitive development on biological world by enriching children’s knowledge through informal and preschool experience

Key words: Naï, ve biology, illness, preschool children