Contradiction intersects with negation and with the formal referential binary true/false. But Freud was especially interested in dynamic processes that allow contradictory mental positions to be maintained simultaneously. In addition to those already mentioned, he also referred to negation linked to repression, disavowal, splitting, and repudiation (or foreclosure, in Lacanian terms). Thus the contradiction between wish and reality is systematic in relation to the difference between the sexes.