The purpose of this investigation was to study the effect of a child's perception of an interrogator upon the child's responses to Piagetian questions of causality. A sample of 463 children aged from 5 to 10 years was interviewed individually to determine their explanation of why clouds move. Subjects were assigned randomly to one of three interview modes: (1) religious, where the interviewer was in clerical dress; (2) nonreligious, where the interviewer was dressed in a business suit; and (3) telephone, where the interviewer was in a distant room. No significant differences were found between the three groups, and Piaget's analysis by stages was broadly confirmed. (MM)