This invention relates to the machine recognition and learning of predetermined categories and more generally, to the representation of patterns, information and knowledge in computational applications. A method of learning categories is an important component of advanced software technology. This invention has applications in the following areas: bioinformatics, document classification, document similarity, financial data mining, goal-based planners, handwriting and character recognition, information retrieval, natural language processing, natural language understanding, pattern recognition, search engines, strategy based domains such as business, military and games, and vision recognition.