Why focus on dirt? Because it is the face of permeation, just as purity is the face of bordering. The ‘matter out of place’ is the proverbial definition of dirt popularized by Mary Douglas half-a-century ago. In general, dirt is THE attribute of the particular and mixed, of transformation and the unpredictable, just as purity and order are the forces of abstraction, segregation, preservation and safe rationality. The permanent struggle between these two poles is what makes our selves. Most of the time we avoid dirt and erase it from perception, but when it manages to capture attention, it hypnotizes. Dirt is the ambiguity that excites and disturbs us to the bones, it is what shapes and shakes the order of things. In this lecture we will dissect the discomfort and excitement of dirt through images and examples, and glimpse into two influential theories (structuralist anthropological by Douglas and psychoanalytic by Kristeva) to outline the permeating powers of dirt (or the dirty powers of permeation, if you prefer).