Structuralism

Lacan drew heavily from the structuralist approach, but he was not a structuralist for two important reasons.

First, while structuralism viewed the subject as a mere effect of symbolic structures, Lacan argued that the subject is not simply reducible to an effect of language and the symbolic order.

Second, for Structuralism, a structure is always complete, while for Lacan the structure - the symbolic order - is never complete. There is always something left over; an excess or something that exceeds the symbolic. What exceeds the symbolic is the subject and the object.