The definition of art has to open up to the question concerning the museum. If one reads the article which Georges Bataille contributed in 1930 in the Documents on the concept of the Museum, one can only be disappointed. From Bataille, the theorist of the heterogeneous, one would have expected something different from seeing in the museum a mirror reflecting a flattering image back to the viewer. It is apparent that visitors to a museum encounter themselves in the museum: an image of human subjectivity. But who wants to maintain that encountering oneself (even if it is broken by irony, as suggested by Bataille’s article) is restricted to the form of self-consciousness and self-appropriation? The category of the heterogeneous has in Bataille’s thinking the function of naming what cannot be appropriated, which Sloterdijk calls the “non-assimilable”. The museum is confronted with what cannot be assimilated. It is a machine for coping with this confrontation. Non-assimilable or heterogeneous would be that which clouds the mirror and distorts its image. Although the museum remains an archive, repository, collection, space of prestigious representation, place of viewing, it is nevertheless already also a laboratory, workshop, generator, machine room, experiment. It cannot be denied that in the museum the familiar combines with the unfamiliar, collection with distraction, the homogeneous with the heterogeneous, ideality with reality. The museum is the place of an irreducible conflict, the space of a turbulence which seems unceasing. As long as the museum-machine still has “chaos within itself” (Nietzsche), it remains the space of unrest of a subjectivity committed to its turbulence. The opening toward chaos does not mean the incorporation of chaos. Chaos is that which blocks its incorporation. And yet, the dynamic form which the museum is is open to chaotic formlessness whilst attempting to make chaos precise. Making chaos precise is the essential work which the museum-machine performs. Making chaos precise means giving space to the non- assimilable, staging the primordial openness of human subjectivity to the space of subject-closure. The museum is the stage for this staging which, instead of being simply a narcissistic staging of the self, brings something alien, unfa miliar, uncanny into play. Therefore, Sloterdijk can define museology as a “form of xenology” which means a form of touching chaos. The xenological character of the museum keeps the museum-machine running. To be open to what is alien means to be open to what is monstrous, faceless, nameless which appears as closure. To give this opening a precision implying a decision and incision requires a certain degree of violence. The museum-machine is not indifferent and it is anything but innocent. It includes and excludes. Optimally it includes what remains exclusive, heterogeneous. Such an inclusion of the exclusive, instead of amounting to its colonial internalization and defusing, would be a form of cooperation with the non-assimilable in its incommensurability. The incommensurable is the ontological concept for the incalculable itself. The museological calculus has to reckon with the incalculable, it has to include in its calculations that which cannot be calculated. The calculus of the incalcu- lable has been thought by Derrida as a form of responsibility which extends itself to that for which responsibility cannot be taken. Like the decision within undecidability, the calculus calculates the incalculable. The logic of this paradox is also the logic of the museum which is already an excess of logic, i.e. of the lógos as collection, because it transcends itself toward an exterior which is the dimension of the heterogeneous. Something resembling a museum exists only as this excess, as museological madness which includes incommensurability by exstituting the institution which the museum represents, thus opening it to an exterior which remains the social, historical, political, economic, cultural reality in its full incommensurability. The question concerning the museum is not merely an incidental question of philosophy. It leads to the question concerning the subject because the subject is a museological machine which carries out the contentious mediation of the past with the future, of certainty with uncertainty, of the familiar with the unfamiliar. That is the diaphoric dimension of human subjectivity. Diaphora means both transport and difference. The museological subject is a transporter of difference who carries the alien to the familiar and the familiar to the alien. The museological machine works at this border between the interior and the exterior, between the comprehensible and the incomprehensible, between form and formlessness. It is another name for life itself, for the life of the subject insofar as the subject is an opening toward the unliveability of life, insofar as, to employ Agamben’s words, it tries to assert itself as a form of living vis-à-vis its naked zoé. The museological machine can be interpreted as an anthropological machine, as an onto-anthropological process. By opening up to the museum, philosophy opens itself to itself. “The museological turn in reinterprets the deepest thought of metaphysics, the ontological difference as described by Heidegger, in the most compact way” (Peter Sloterdijk).The ontological difference between being and beings is described by Heidegger as diaphora, as processual compossibility of the non-compossible, as “the unifying element”. That is what connects the museological machine with the anthropological machine: the opening to a difference marking the rupture between interior and exterior, sayable and unsayable, language and silence. Strictly speaking, this rupture does not exist because it belongs neither to the register of beings (of that which exists) nor to the register of being (which denotes the ground of being of beings). The diaphoric rupture between being philosophy must not be confused with a transition into another genus; it has nothing to do with an evasion into areas with lower standards. It remains in the precise sense of the word philosophical because it reinterprets the deepest thought of metaphysics, the ontological difference as described by Heidegger, in the most compact way.” The ontological difference between being and beings is described by Heidegger as diaphora, as processual compossibility of the non-compossible, as “the unifying element”. That is what connects the museological machine with the anthropological machine: the opening to a difference marking the rupture between interior and exterior, sayable and unsayable, language and silence. Strictly speaking, this rupture does not exist because it belongs neither to the register of beings (of that which exists) nor to the register of being (which denotes the ground of being of beings). The diaphoric rupture between being and beings is an empty place which Agamben defines as the “zone of indeterminacy”, as “the place of a ceaselessly updated decision in which the Caesurae and their rearticulation are always dislocated and displaced anew”. The anthropo-museological machine would be this place of constant decisions which generates equally homogeneities, coherences, connections, interdependencies as well as calling them into question, suspending and dissolving them. A machine which produces continuities and discontinuities at one and the same time, an equally precise as well as crazy generator demonstrating itself in the image of headless subjectivity. To be a subject means to be such a machine which with the required exactness remains turned toward chaos, the future, what is coming, toward contingency. The human subject is a subject without subjectivity because it is a machine whose programming does not pre-exist. Only in retrospect to the events, experiences and encounters generated by this machine does a continuum of sense, a causality, become legible which at the moment of its legibility already no longer holds. The continuity of the museological machine lies in its discontinuity, just as the essence of the subject is based on its lack of essence. The museological excess means the originary self-transcendence of instituted, recorded, archived reason toward its constituted exterior which is not that which is simply external to it but that which persists at its centre. The museum as excess provides an ontological concept of human existence as a subject originarily transgressed and transcended toward the desert of incommensurability