The objective of the study was to explore how social mindies or the process social units of mind, social interaction, and private and public behavior are related in the time interval between 13 and 16 years of age. A "mindy" is a unit process of mind constructed through using a mental shape as a sketch for mindy processing. A social mindy is a mindy that channels social interaction into a conservative rut. Conservatism of social interaction produces a divergence from public and private behavior during the years from 13 to 16. The subjects were 106 secondary comprehensive school students in Finland. An axiom of mindy was constructed based on results of previous studies, and a hypothesis was derived from the axiom. Three questionnaires were constructed for variables other than the social mindies, which were measured with a developed test. The reliability and validity of the measures were evaluated. The dynamic evaluation included an application of the Bayes tree for the calculation of conditional probabilities. The hypothesis was not corroborated and the results seemed merely serendipitous. Results indicate the existence of a trim effect and dicausalities between the variables. In addition, results indicate that social behavior can be ostensible and that during the time between ages 13 and 16 subjects become perplexed with the social environment. An educational application for teaching social skills and a further refinement of educational theory are presented. (Contains five tables, one figure, and six references.) (Author/SLD)