Graham Harman explains Meillassoux's correlationism critique.

The correlationist argument, often left vague or entirely unstated, holds that any attempt to think reality-in-itself automatically turns it into something not in-itself-since, after all, we are now thinking about it. On this basis, there is supposedly no way to reach the world an sich, but only a global correlation of human and world. Philosophy has lost what Meillassoux calls Le Grand Dehors, "the Great Outside." In its place, we find that "this space of the outside is hence only the space of that which faces us, of that which exists only on the basis of a vis-à-vis with our own existence.... We do not transcend very far beyond ourselves when diving into such a world: we are content to explore the two faces of something that remains a face-to-face". This correlate need not take the form of the old subject/object dualism. Indeed, most present-day philosophers unite in heaping scorn upon the antiquated model of subject and object. But this does not prevent them from remaining locked in the modern dance-step of correlationism. In particular, Meillassoux cites Heidegger's supposedly "more originary" correlation of being and thought in Ereignis as an example of how the rejection of subject and object does not quite get us off the correlationist hook. As Meillassoux sees it, all postcritical philosophy is correlationism - or else a relapse into metaphysics, as with Whitehead and perhaps even the vitalism of Deleuze. Before Kant, philosophers dueled over who had the best model of substance: was it perfect forms, individual beings, prime matter, atoms, or God? Since Kant, these "naïve" disputes have been replaced by combat over who has the best model of the human-world correlate: is it subject-object, noesis-noema, Dasein-Sein, or language-referent? In Meillassoux's eyes, "co" has become the dominant particle of the philosopher's lexicon, just as "always already" has become the beloved phrase of those who grant extra-human reality only when we ourselves posit it retroactively. Yes, they tell us, the world exists in itself-but only for us.

[Original 8:40 AM]
[Bumped 2:06 PM. Read also Avoiding Correlationism wherein Clark correlates the above to Kant and Peirce.]  ¶ 2:04 PM