From there he moved to become the Director of Philosophy at the University Paris X – Nanterre, and in 1991 also took up the role of professeur invité at the Institut Catholique de Paris. In 1996 he became Director of Philosophy at the University of Paris IV (Sorbonne), where he still teaches.
Marion became a visiting professor at the University of Chicago Divinity School in 1994. He was then appointed the John Nuveen Professor of the Philosophy of Religion and Theology there in 2004, a position he held until 2010. That year, he was appointed the Andrew Thomas Greeley and Grace McNichols Greeley Professor of Catholic Studies at the Divinity School, a position that had been vacated by the retirement of theologian David Tracy.
According to John D. Caputo, Marion "is famous for the idea of what he calls the “saturated phenomenon,” which is inspired by his study of Christian Neoplatonic mystical theologians....[The idea that] there are phenomena of such overwhelming givenness or overflowing fulfillment that the intentional acts aimed at these phenomena are overrun, flooded—or saturated."
The fourth section of Marion's work Prolegomena to Charity is entitled "The Intentionality of Love" and primarily concerns intentionality and phenomenology. Influenced by (and dedicated to) the French philosopher Emmanuel Levinas, Marion explores the human idea of love and its lack of definition: "We live with love as if we knew what it was about. But as soon as we try to define it, or at least approach it with concepts, it draws away from us." He begins by explaining the essence of consciousness and its "lived experiences." Paradoxically, the consciousness concerns itself with objects transcendent and exterior to itself, objects irreducible to consciousness, but can only comprehend its 'interpretation' of the object; the reality of the object arises from consciousness alone. Thus the problem with love is that to love another is to love one's own idea of another, or the "lived experiences" that arise in the consciousness from the "chance cause" of another: "I must, then, name this love my love, since it would not fascinate me as my idol if, first, it did not render to me, like an unseen mirror, the image of myself. Love, loved for itself, inevitably ends as self-love, in the phenomenological figure of self-idolatry." Marion believes intentionality is the solution to this problem, and explores the difference between the I who intentionally sees objects and the me who is intentionally seen by a counter-consciousness, another, whether the me likes it or not. Marion defines another by its invisibility; one can see objects through intentionality, but in the invisibility of the other, one is seen. Marion explains this invisibility using the pupil: "Even for a gaze aiming objectively, the pupil remains a living refutation of objectivity, an irremediable denial of the object; here for the first time, in the very midst of the visible, there is nothing to see, except an invisible and untargetable void...my gaze, for the first time, sees an invisible gaze that sees it." Love, then, when freed from intentionality, is the weight of this other's invisible gaze upon one's own, the cross of one's own gaze and the other's and the "unsubstitutability" of the other. Love is to "render oneself there in an unconditional surrender...no other gaze must respond to the ecstasy of this particular other exposed in his gaze." Perhaps in allusion to a theological argument, Marion concludes that this type of surrender "requires faith."
God Without Being, University of Chicago Press, 1991. [Dieu sans l'etre. Hors-texte, (1982)]
Reduction and Givenness: Investigations of Husserl, Heidegger and Phenomenology, Northwestern University Press, 1998. [Réduction et donation: recherches sue Husserl, Heidegger et la phénoménologie, (Paris: Presses Universitaires de France, 1989)]
Cartesian Questions: Method and Metaphysics, University of Chicago Press, 1999. [Questions cartésiennes I: Méthode et métaphysique, (Paris: Presses Universitaires de France, 1991)]
'In the Name: How to Avoid Speaking of 'Negative Theology', in JD Caputo and MJ Scanlon, eds, God, the Gift and Postmodernism, (Bloomington, IN: Indiana University Press, 1999)
On Descartes' Metaphysical Prism: The Constitution and the Limits of Onto-theo-logy in Cartesian Thought, University of Chicago Press, 1999.
The Idol and Distance: Five Studies, Fordham University Press, 2001. [L'idole et la distance: cinq études, (Paris: B Grasset, 1977)]
Being Given: Toward a Phenomenology of Givenness, Stanford University Press, 2002. [Étant donné. Essai d'une phénoménologie de la donation, (Paris: Presses Universitaires de France, 1997)]
In Excess: Studies of Saturated Phenomena, Fordham University Press, 2002. [De surcroit: études sur les phénomenes saturés, (Paris: Presses Universitaires de France, 2001)]
Prolegomena to Charity, Fordham University Press, 2002.
The Crossing of the Visible, Stanford University Press, 2004.
The Erotic Phenomenon: Six Meditations, University of Chicago Press, 2007. [Le phénomene érotique: Six méditations, (Paris: Grasset, 2003)]
On the Ego and on God, Fordham University Press, 2007.
The Visible and the Revealed, Fordham University Press, 2008.
Descartes' Grey Ontology: Cartesian Science and Aristotelian Thought in the Regulae, St. Augustine's Press, 2012.
Descartes' White Theology, Saint Augustine's Press, Translation in process.