In philosophy, the last thirty years or so has seen a split between 'simulation theorists' and 'theory-theorists', with a number of variations on each side. In general, simulation theorists favour the idea that our knowledge of others is based on using ourselves as a working model of what complex psychological creatures are like. Theory-theorists claim that our knowledge of complex psychological creatures, including ourselves, is theoretical in character and so more like our knowledge of the world in general. The body (...) of this paper is divided into three parts. In Part I, I introduce the 'contrastive case' of autism. Autism is a developmental disorder that has recently become the focus of sustained philosophical and psychological attention because of the selective way in which it affects individuals' social capacities. Theory-theorists argue that autistic children's unique profile of assets and deficits is most fruitfully explained by their inability to develop and deploy a theory of mind. After considering the strengths of this hypothesis, I claim theory-theorists face two unresolved difficulties: explaining why high-functioning autistics who develop some theory of mind capacities still fail to engage in normal psychological knowing; and explaining why autistics are generally as unknowable to us in the privileged sense of normal psychological knowing as we are to them. In Part II, I provide the theoretical framework for addressing these challenges by developing an account of normal psychological knowing as psycho-practical expertise. In Part III, I return to the problem of autism, showing how this psycho-practical approach to normal psychological knowing may further suggest how to encompass various aspects of the disorder that tend to be ignored under the prevailing theory-theory approach. (shrink)