An Effect which Retroactively Posits its own Cause

From the glossary in Sarah Kay’s Žižek:  A Critical Introduction (Cambridge, UK: Polity Press), p. 159.

APRES-COUP:  The psychoanalytical view of time is that it does not progress in a linear way but in a kind of backward loop, so that the crucial tense is the future perfect:  what ‘will have been’.  For example, a childhood experience will reveal itself to have been traumatic if it is reactivated as such--for example, in a neurotic symptom--by some subsequent turn of events.  The concept of après-coup does not mean that the past does not determine the present--it does, but in a way that is itself overdetermined by the present.  Thus significance is always grasped retrospectively.  An elementary effect of après-coup is that it is not until the end of a sentence that the meaning of its beginning can be ascertained.  A more complex instance is that the SUBJECT, which is nothing but the failure of S1 to represent it to S2, is nevertheless perceived as what will have been filled out by S2 (see SIGNIFYING CHAIN).  For this reason, the subject is said to be an effect which retroactively posits its own cause.  There is nothing teleological about après-coup; the point is that what may seem inevitable is a purely contingent state of affairs.  The process of après-coup shapes Lacan’s reading of Freud and Žižek’s readings of both Lacan and Hegel:  each reader reveals from his or her own, contingent viewpoint ‘what’s in the text which could not be written there’ (‘Lacan in Slovenia’, 26).