The paper reports a research study on adults' epistemological beliefs, i.e., on the nature of knowledge and knowledge acquisition. We were especially interested in the possible relation between adults' epistemological belies and their instruction level, age and knowledge mastery. With this aim in mind, a sample of 171 adults of different ages (age range 24 to 60 years) and education levels were
... [Show full abstract] divided into three groups: without university studies, university graduates. and Secondary Education teachers. They answered three closed questionnaires in which they were asked to what extent they agreed to statements about certainty, epistemological criteria, and knowledge acquisition involving three different knowledge domains: Natural Science, Social Science and Moral Knowledge. They were also asked to justify their choices. The answeres were analysed according to the degree of agreement with objectivist, relativist or constructivist positions. The results showed that in adults there is a transition between objectivism and constructivism. Adults tended to show greater epistemological sophistication-closer to constructivism- in tasks requiring only that they speficy their degree of agreement than in those requiring an explicit response and justification of their position. We found also an effect of subjects' instructional level, i.e., adults with university studies and, above all, Secondary Education teachers showed significantly greater constructivism. Concerning age, older adults held more objectivist positions, whilst younger adults were closer to relativist beliefs, especially in the Moral domain. In contrast, objectivist positions were in general more common in the natural and social science domains.