This work focuses on three topics: the social value of motor cognition (i.e. experimental studies in human and non-human primates showing that the parieto-frontal mirror circuit plays a crucial role in action understanding before and below mindreading abilities); motor encoding of action anomalies in individuals with autism spectrum disorder that may explain – to a degree – their limited social abilities; failure of social agreement resulting in criminal actions that may be clarified thanks to neuroscience data in forensic psychiatric evaluation. Describing the role of experimental data – notably the functional role of cortical motor system – in clarifying social experience, this work reverses also the way in which we consider ourselves as agents in social interactions. This work focuses on behaviours, brain and concepts. This work draws a synergetic view integrating conceptual, experimental, clinical and forensic perspectives. This work, for saving phenomena, forces the categories.