For Heidegger, all sciences belong to and continue the metaphysical tradition of forgetting the question of the being of beings. For Lacan, every proper science means a break against, within and in regard to the metaphysical tradition of philosophy. From a Heideggerian perspective, Lacan is unable to see the metaphysical implications and presuppositions of all the sciences. From a Lacanian perspective, Heidegger’s interpretation of a science is, in the end, naive and totalitarian. In other words, Heidegger includes all discourses into the totality formed by the history of the question of (the meaning of) the being of beings. Besides this, Heidegger includes all sciences into a homogenic and homological group, the totality of science, which seems to be, not only a coarse judgment, but also simply a totally blind and incompetent misjudgment. In Lacanian jargon, this means that Heidegger himself presupposes the Other of the Other: for Heidegger, the question of the being of beings functions, in the last analysis, as the Other of the Other criticized by Lacan. For Lacanians, what is radical in sciences is their ways of constructing discourses through formalized languages, not some determined “scientific” proposition. This is why Lacan stresses again and again that psychoanalysis is a science, and not only whatsoever science, but the science of the subject of science. The subject psychoanalyses studies is the subject of signifiers approached formally as signifiers, without their signified. Psychoanalysis as Lacan sees it became possible only after scientific revolutions. From this perspective, psychoanalysis is always secondary in regard to scientific revolutions.