Traditional social science often fails when deployed to explain complex human action. In each specific social field of human endeavour, including planning, experienced actors draw on a range of conscious and unconscious performative knowledges to act with effect: the experts simply ‘know’ what to do. Flyvbjerg suggests that to understand these complex human dispositions framing practice requires a detailed understanding of the particular, not the universal. Drawing on Aristotle's intellectual virtue of phronesis, Flyvbjerg refers to this as a phronetic social science model. This article suggests that Lacan's theoretical insights and conceptualizations pertaining to the split human subject, divided between symbolic consciousness and unconscious affect, can help to empower this phronetic model. The article argues that a Lacanian inspired phronetic model is particularly useful for understanding spatial planning and related urban policy discourses, for it provides insight as to how desire and resultant ideological fantasies shape our shared social reality and spaces of habitation in our globalized world.