Critchley on Heidegger's Being and Time, Part 4

From a series of articles published in The Guardian
Caspar David Friedrich, 'Monk by the Sea' (1809-10)
The fourth Simon Critchley article on Heidegger's Being and Time has been published today on The Guardian website:
As I already tried to show, Heidegger seeks to reawaken perplexity about the question of being, the basic issue of metaphysics. In Being and Time, he pursues this question through an analysis of the human being or what he calls Dasein. The being of Dasein is existence, understood as average everyday existence or our life in the world, discussed in the last entry. But how might we give some more content to this rather formal idea of existence?

Heidegger gives us a strong clue in Division 1, Chapter 5 of Being and Time, which is a long, difficult, but immensely rewarding chapter and where things really begin to get interesting. The central claim of this chapter - which is deepened in the remainder of Being and Time - is that Dasein is thrown projection (Dasein ist geworfener Entwurf). Let me try and unravel this thought.

Read part one: 'Being and Time, part 1: Why Heidegger matters'.