mythical story, it takes and gives back this complexity of sense. This complexity, or more precisely, this ' polyvalence ', can be observed on a synchronic level (that is, many senses for the same 'image' in [...] Consequently, reading the Greek mythology is similar to reading a language, in which the basic part (the ' image ') is the issue of the fusion between a signifier and a signified - that is between [...] casting stones over their shoulders ( hyper kephales eballen airon lithous ) from which people springs [18] . Then, at Troezen Lithobolia becomes a real ritual and festival, an heorte ,