This paper develops a formal information structuring model based on the premise that an information system represents knowledge about things in an organization. Since humans organize knowledge about things via categories or classes, the model is motivated by a theory of classification. The theory suggests several critical elements of classification based on the importance of classifying things to human survival. These elements are reflected by constructs in the model. Formal implications of the model for systems development are derived and strategies proposed for empirically evaluating these implications with respect to current modeling approaches. Necessary conditions are identified for a collection of classes to be considered a ‘good’ model of some domain. The conditions permit different users to classify the same objects in different ways, depending on need. This suggests a new approach to data or object modeling which emphasizes instances and properties, rather than fixed categories of data or schemas. The model also offers insights into the role of classification in object-oriented analysis and design methodologies. Finally, a program of research is outlined in which the model is being used to develop and experimentally evaluate an information modeling methodology, and as a source of implementation primitives for ‘instance-based’ data modeling.
