How we change what others think, feel, believe and do
Différance is a word created by Derrida to explain a concept where opposites interact and meaning becomes unstable.
Words often have opposites which, far from being independent terms, need the other to complete the definition. Thus black is not a clear concept without white, up without down, etc.
Différance is the gap between the signifier and the signified. The one is not the other, yet they are inextricably linked.
In saying 'black', you must consider white. Black thus includes the 'trace' of white within itself. Thus, when meaning settles on black, white is inferred and intrudes to corrupt the blackness of the initial meaning. And as the thought shifts to white, so also is black re-triggered. Meaning is thus unstable and constantly being slipped and deferred.
Words are often taken to have fixed meaning, yet in use their meaning is highly context dependent and ultimately depends on individual interpretation.
Words also contain associations and derivations that link them to other words and meanings. Rather than a fixed meaning, a word has a field of meanings, and in any usage, even with contextual narrowing, there is a 'surplus of meaning'.
Further to the basic différance of opposites, as in the Lacan's sliding signifiers, any association that other a person has with black may also be triggered.
Thus any thought of 'I' leads to associated and opposite concepts, making identity an unstable concept. For Derrida, self-presence is a position, not a unity. To think about 'I' is also to think about the 'other'. It also shifts position to the 'I' of the other, such that the original 'I' now becomes an 'other'. When we claim identity, we are trying to stabilize this ambiguous shifting.
Différance is almost Taoist in its intertwining of opposites, where the yin-yang symbol has a white spot in the center of the black, and vice versa, thus symbolizing how in one thing lies the seeds of the opposite.
Words in critical theory are often used in non-normal ways. Stuart Hall points out how it is as if a deliberate distortion of the language is being used to destabilize the reader's understanding, shaking them into new possibilities without altogether losing previous meanings.
Thus 'différance' with an 'a' is suspended between the French verbs to differ (être différent) and to postpone (différer). When meaning is shaken, then what is intended can be hard to pin down, forcing the reader to search further. This is almost Lacanian in the tension that is created between unity and separation.