Although Lacan's rejection of dualistic schemas in favour of an emphasis on the triangular structure of the symbolic involves a predominance of triadic schemes in his work, Lacan also insists on the importance of fourfold schemes:
The emphasis on the quaternary first comes to the fore in Lacan's work in the early 1950s, and is perhaps due to the influence of Claude LÈvi-Strauss, whose work on the structure of the avunculate shows that the basic unit of kinship always involves a minimum of four terms.
Thus, in a 1953 paper which deals with the neurotic's 'individual myth' (another reference to Levi-Strauss), Lacan remarks that "there is within the neurotic a quartet situation," and adds that this quartet can demonstrate the particularities of each case of neurosis more rigorously than the traditional triangular thematisation of the Oedipus complex.
Thus, in addition to the three elements of the Oedipus complex (mother, child, father), Lacan often speaks of a fourth element; sometimes he argues that this fourth element is death, and at other times he argues that it is the phallus.
Other important quaternary structures which appear in Lacan's work are schema L (which has four nodes), the four partial drives and their four corresponding part-objects, and the four discourses (each of which has four symbols assigned to four places).
Lacan also enumerates four "fundamental concepts of psychoanalysis" and speaks of the sinthome as a fourth ring which prevents the other three rings in the borromean knot (the three orders of the real, the symbolic and the imaginary) from becoming separated.
- Lacan, Jacques. Écrits. Paris: Seuil, 1966. p. 774
- Levi-Strauss, 1945
- Lacan, Jacques. 1953b: 231
- Lacan, Jacques. 1953b:232
- Lacan, Jacques. 1953b: 235
- Lacan, Jacques. 1953b: 237; S4, 431
- Lacan, Jacques. The Seminar. Book III. The Psychoses, 1955-56. Trans. Russell Grigg. London: Routledge, 1993. p.319
- Lacan, Jacques. Écrits: A Selection. Trans. Alan Sheridan. London: Tavistock Publications, 1977. p.139, 229-230
- Lacan, Jacques. 1955a
- Lacan, Jacques. 1964a