In this paper I propose to do the following: I will discuss the notions of intentionality and self-understanding of Dasein as developed in Heidegger's Basic Problems of Phenomenology. In doing so, I will try to show the interrelation of Dasein's always being intentionally directed towards something and its self-interpretation. As we will see, the everyday world has, for Heidegger, a character of "equipmental contexture." This means that Dasein returns to itself from out of things, equipment, tools, or - quite differently - the work of art. In a word, Dasein is mirrored back toward itself from the things made, from the products of techne. From this will follow the important distinction between authenticity and inauthenticity. There is a sens...