There are important and interesting conceptual links between Brouwer's intuitionism and Husserl's transcendental phenomenology. This is true independently of whether or not there had ever been a historical intersection of the two approaches to mathematics and logic. But of course there was a historical intersection. It occurred primarily in the nineteen twenties and early thirties, in the middle of the foundational debate between Brouwer's intuitionism and Hilbert's formalism. During this period there is a fascinating development and exchange of ideas on intuitionism, phenomenology, and formalism in the work of Hermann Weyl, Oskar Becker, Felix Kaufmann, and Arend Heyting, which is set against the background of the ideas of L.E.J. Brouwer, Edmund Husserl and David Hilbert¹.