Derrida began his career examining the limits of phenomenology. His first lengthy academic manuscript, written as a dissertation for his "diplôme d'études supérieures" and submitted in 1954, concerned the work of Edmund Husserl. Gary Banham has said that the dissertation is "in many respects the most ambitious of Derrida's interpretations with Husserl, not merely in terms of the number of works addressed but also in terms of the extraordinarily focused nature of its investigation." In 1962 he published "Edmund Husserl's Origin of Geometry: An Introduction", which contained his own translation of Husserl's essay. Many elements of Derrida's thought were already present in this work. In the interviews collected in "Positions" (1972), Derrida said: "In this essay the problematic of writing was already in place as such, bound to the irreducible structure of 'deferral' in its relationships to consciousness, presence, science, history and the history of science, the disappearance or delay of the origin, etc. [...] this essay can be read as the other side (recto or verso, as you wish) of "Speech and Phenomena"."