The 7 day week is still most evidently felt within the domain of work. As opposed to hunter gatherer societies, modern workers are in a pattern of temporal regularity that is essentially artificial, not dictated by daily variations between the quality of vision between night and day, seasonal variations in temperature or amount of rain, and so on. The artificiality of the modern "work /rest" beat results from the fact that it is dissociated from most natural rhythms, being largely derived from a mechanical periodicity.