Video data from three large captures of choreographic dance making was analyzed to determine if there is a difference between participant knowledge – the knowledge an agent acquires by being the cause of an action – and observer knowledge – the knowledge an observer acquires through close attention to someone else’s performance. The idea that there might be no difference has been challenged by recent findings about the action observation network and tacitly challenged by certain tenets in enactive perception. We (...) explored why a choreographer ‘riff’s’ when appropriating and evaluating the movements of his dancers. By recruiting his body to help him cognize he is able to understand the possibilities of movement better than observation. He acquires participant knowledge. (shrink)