Thee Pound Brain has a good post up analyzing Speculative Realism and Levi Bryant's Object-Oriented Ontology in particular. Reading it is like being at the Mad Hatter's tea party (which is jolly good fun). In particular, I note this passage:
It’s a good rule-of-thumb, I think most will be inclined to agree, to be incredulous of any systematic set of claims that argues against incredulity. But this is precisely what Bryant does in arguing that, even though all his claims are in fact conditioned by his cognitive capacities, personal history, social context, and so on, one should pretend all these potential confounds are out of play. There is no question more honest than, “How do you know?” yet he would have us relegate it on the basis of speculation that, coincidentally enough, has no way of answering this very question.
I have addressed this issue before and argued against recourse to transcendental arguments to find certain knowledge. Even Kant noted that his arguments had the duality of being empirically real but transcendently ideal, while the modern version of transcendental argumentation, abduction, proposes only scientific hypothesis and speculative metaphysics.