This discussion reviews the psychoanalytic and developmental psychological theories that utilize nonlinear dynamic systems theory to situate Sperry's paper in its theoretical and historical context. The power of such nonlinear models for clinical work and theories of mind is argued. The essay then argues that the shift in theory entails a shift in ways of clinical writing and that the clinical discussion in the paper does not always feel consonant with the theory. Moving to a model of nonlinearity, intersubjectivity, and uncertainty is likely to entail shifts in conceptualizing and conveying clinical material.