This work deals with Lacan's turn to the topological writings of nodality. To the Borromean knot of three rings Lacan adds a supplementary ring, le sinthome, defined in its function as a letter. According to it, it is le sinthome which permits the symbolic, the imaginary and the real to stay together, due to two errors, two points in the structural fault which are produced in the intertwining of the imaginary and the symbolic: the point of the lapse, the fundamental mistake, the no-sense, where the symptom-metaphor lies; and the point of the primordial fault, where le sinthome lies in its function of enjoyment and fault supplementation.
Point of the lapse; point of the primordial fault; symptom-metaphor; le sinthome
