In The Concept of Time Heidegger introduces many of the central themes of his analyses of human existence which were subsequently incorporated into Being and Time , themes such as Dasein, Being-in-the-world, everydayness, disposition, care, authenticity, death, uncanniness, temporality and historicity. Starting out by asking: What is time?, Heidegger proceeds to radicalise the concept of time and our relation to it, ending with the question: Are we ourselves time? Am I time?