Heidegger writes in What is Philosophy that destruction does not mean destroying but dismantling, liquidating, putting to one side the merely historical assertions about the history of philosophy.
The task of philosophy is now designated by Heidegger to overcome the history of metaphysics, which has trapped philosophy in representational thinking and Platonism. In place of metaphysics as representation or logos, Heidegger writes that philosophy should be an inquiry of the being of Being, thus moving philosophy beyond metaphysics into the realm of ontology. The history of metaphysics, or ancient ontology, has to be overcome as it inaccurately creates a division between ideal and real, subject and object. Heidegger argues that these are conflated in Being. Being is the founding condition of possibility and ontological ground for both. The end of philosophy signals the end of metaphysics as ancient ontology, or representational thought which presents a perfect correlation between essence and existence, concept and reality, because these are conflated in Being. Being is the ground of possibility for thinking both. Essence and existence are united in Being. As Heidegger argues in The End of Philosophy:
If the questions raised are thought through even thoroughly, the illusion of being as a matter of course, in which the distinction of essentia and existentia stands for all metaphysics, disappears. This distinction is groundless if metaphysics simply tries again and again to define the limits of what is divided, and comes up with numbering the manners of possibility and the kinds of actuality which float into vagueness, together with the difference in which they are already placed.
Heidegger argues that the distinction between essentia and existentia that has held throughout the history of metaphysics presents an illusion and becomes groundless as both are united in Being. Being is the ontological ground of both and thus precedes both.
Heidegger argues that metaphysics has sustained itself through an illusory distinction between whatness and thatness, or ideal and real. Heidegger argues that Being, or thatness, makes possible the essence of Being, or whatness, hence metaphysics has proceeded along failed presuppositions. In Being, whatness and thatness are united, Being translates as the ontological pre-condition that determines both. Truth as metaphysics, which has sustained itself through the illusory distinction between whatness and thatness, has thus approached its end. Heidegger argues that the task of thinking becomes to rethink truth as aletheia, or the disclosure of Being as truth. Truth has to be rethought as the unconcealing of Being as aletheia, rather than as a concealment as the Greeks such as Plato and Aristotle have interpreted it. Heidegger’s conflation of essence and existence in Being does nothing to alter the fundamental structure of metaphysics which he borrows from and thus affirms. Rather, Derrida’s notion of iterability, traces the condition of possibility for the production of both through the distinguishing trace of difference. This goes beyond Heidegger’s collapsing of this distinction into the singular Being in examining the meta-conditions in which essence and existence are produced. An inversion or negation of metaphysics repeats it by borrowing its ontological structure and vocabulary, according to Derrida. Heidegger’s destruction of metaphysics is thus a repetition of metaphysics in every sense of the word as a negative metaphysics remains a form of metaphysics, repeating its structure and vocabulary. In showing that metaphysics and post-metaphysics share the same ontological vocabulary,
Derrida demonstrates that there is no difference between metaphysics and Heidegger’s postmetaphysics.
Heidegger names the essence of Being as existence, but this is merely a reversed metaphysics which repeats the ontological structure of metaphysics, just as conflating existence and essence in Being borrows from the ontological structure of metaphysics and thus remains metaphysics. Heidegger requires the transcendental to be excluded and accounted for on empirical grounds in order to maintain his situated realm of Being. Heidegger thus excludes the quasi-transcendental, or transcendental-empirical difference, which is precisely what he needs to maintain his philosophy. Were there no quasi transcendental or written mark, it would be impossible to designate as Heidegger does, a pure realm of empirical signs. Heidegger thus needs to acknowledge this quasi-transcendental that he needs in order for his empiricism to function and thus inscribe his phenomenology in a more powerful way as Derrida would suggest.