Competence comes only after considerable experience actually coping with real situations in which the student notes or an instructor points out recurrent meaningful component patterns. These situational components, in terms of which a competent student understands his environment, are no longer the context-free features used by the novice. We will call these recurrent patterns aspects. Aspect recognition cannot be produced by calling attention to recurrent sets of features, but only by singling out perspicuous examples. [...] The instructor can formulate principles dictating actions in terms of these aspects. We will call such principles, which presuppose experience-based meaningful elements, guidelines. The guidelines treat all aspects as equally important and are formulated so as to integrate as many aspects as possible.
Stuart E. Dreyfus, Hubert L. Dreyfus. A five-stage model of the mental activities involved in directed skill aquisition. 1980
