Speaking generally, however, when you interact with someone else, you are doing outer work (physical time, play time, connecting time) ... as many sociologists have pointed out, this area of life used to dominate everyday existence, at a time when families sat around the fire of an evening and ate every meal together. That's no longer true. Families today are often loose constellations. Contact is intermittent and rushed. everyone has their own space. Activity is scattered all around town, not confined to the home. Cars have made everyone mobile, but central heating may be the most powerful force in shaping modern society.