The sex/gender binary has proven to be a profoundly useful conceptual distinction in the furthering of the feminist project. It has also been a controversial opposition that has given rise to an ongoing and productive debate. In this article we utilise neuroscience, specifically a text by the neuropsychologist Elkhonon Goldberg, to trouble this binary in the hope of furthering the critical project. We argue that a cautious negotiation with the biological may be theoretically and politically productive. By taking seriously Goldberg’s notions of functional-morphological and corporeal-environmental intimacy in reading his claim of distinct gender-based cognitive styles it is possible to glimpse the variation of sex itself. This, we argue, demonstrates both the limits of binaries and celebrations of difference and reveals the complexity which we have to negotiate in the search for emancipatory change.