<human>:  In Heidegger’s Being and Time, how does he define the concept of Dasein?
<bot>: Dasein is a term that Heidegger uses to refer to the human subject. In Being and Time, Heidegger argues that Dasein is always already “thrown” into the world, and that the world is not simply a physical place but rather a place that we inhabit. He also argues that Dasein is always in the process of being itself, and that the world is not simply a set of objects that exist independently of us.