by quite different examples, three basic functions of metaphors: illustrative, heuristic~ and constitutive. These functions rep­ resent different degrees of transfer of meaning. Metaphors are illustrative when they are used primarily as a literary device, to increase the power of conviction of an argument, for example. Although the difference between the illustrative and the heuristic function of metaphors is not great, it does exist: metaphors are used for heuristic purposes whenever "differences" of meaning are employed to open new perspectives and to gain new insights. In the case of "constitutive" metaphors they function to actually replace previous meanings by new ones. Sabine Maasen in her paper introduces the distinction between transfer and transforma­ tion.