This essay explores the semiotic mystery tour at the heart of psychoanalytic free association. Its quest is to contemplate what remains unspoken and unsymbolized by our patients’ claims of “having no thoughts.” The author follows associations in the psychoanalytic literature that reveal an often hidden link between having “nothing” to say and the missing presence of an obscured, if not invisible, female genital. Naming “the gaps” in free association is how we conceive and know unspeakable truths, an otherwise inconceivable reality. The “gap” or “space” in free association obscures and points to the unsignified female genital. Situated between physical actuality and spatial abstraction, the female genital is essential to free association’s path and must be named. The author proposes a “feminine law,” affirming the primacy of this generative, vaginal space as signifying the mysteries of female power and of unconscious knowledge.