Heidegger argues that our fundamental experience of the world is one of familiarity. We do not normally experience ourselves as subjects standing over against an object, but rather as at home in a world we already understand. We act in a world in which we are immersed. We are not just absorbed in the world but our sense of identity, of who we are, cannot be disentangled from the world around us. We are what matters to us in our living; we are implicated in the world.
Heidegger’s Being and Time