Author's personal copy 164 scientific practice (Achinstein 1968; Hesse 1966; Harré 1970), as well as investigating what role analogies and metaphors play in the construction of models (Black 1962; Hesse 1966) or of other components, linked to these, raised by historicist philosophers, such as exemplars (Kuhn 1970). At the present time, the importance of models in scientific practice is being emphasized. The semantic view-which deals with the subject matter of models within the framework of a general conception of scientific theories-is being imposed as an alternative to the classical and historicist views of scientific theories, 1 and model views of science are being developed-which deal with questions of the relationship between models and experience and between models and general theories independently of a general metatheory of science (