Obstruent Obstruent An obstruent is a speech sound such as , , or that is formed by "obstructing" airflow. Obstruents contrast with sonorants, which have no such obstruction and so resonate. All obstruents are consonants, but sonorants include both vowels and consonants. Obstruents are subdivided into plosives (oral stops), such as , with complete occlusion of the vocal tract, often followed by a release burst; fricatives, such as , with limited closure, not stopping airflow but making it turbulent; and affricates, which begin with complete occlusion but then release into a fricative-like release, such as . Obstruents are prototypically voiceless, but
The Instance of the Letter in the Unconscious, or Reason Since Freud language is not a superstructure'. Lacan uses his concept of the letter to distance himself from the Jungian approach to symbols and the unconscious. Whereas Jung believes that there is a collective unconscious which works with symbolic archetypes, Lacan insists that we must read the productions of the unconscious "à la lettre" - in other words, literally to the letter (or, more specifically, the concept of the letter which Lacan's essay seeks to introduce). In Freud's theory of dreams, the individual's unconscious takes advantage of the weakened ego during sleep in order to produce thoughts which have been censored during