Before performing exploratory surgery on the beating heart of OOP, it is first necessary to present the customary compliments regarding the overall shape and style of its vascular architecture. Whatever else may be said about Harman’s presentation of OOP, it is certainly compelling. On the one hand, it attempts to reveal the inherent oddness of the world in which we live, depicting a reality in which everything is radically individual, cut off from everything else in almost every respect, connected only by fleeting glimmers of phenomenal appearance. On the other, it attempts to humble humanity by seeing humans as just one more disparate association of objects within the universal diaspora, and the intentional terms through which they relate to one another as merely an expression of a more fundamental sensual connectivity in which everything may partake. Such willingness to countenance counterintuitive metaphysical conclusions and to embrace ontological humility is to be applauded.
Moving on, the central axis around which Harman’s metaphysical system turns is the distinction between the real and the sensual. He is fond of describing this by appealing to a volcanic metaphor: the reality of things consists in their ‘molten cores’, the liquid specificities of which withdraw behind a ‘sensual crust’ of visible features. On this view, the substantial magma at the heart of every entity is forever trapped beneath a rocky outer surface whose stillness is only occasionally interrupted by the tectonic forces it unleashes. However, these occasional eruptions always catch us unawares. We never glimpse the molten essence as it leaks through the faultlines in its phenomenal facade, but only catch it as it cools, already crystallising into new sensual continents. The lava itself is nowhere to be found. To twist this metaphorical register for the purposes of summary: Harman’s is a world of disconnected volcanic island nations floating in a cool sensual sea—a world in which you can travel as much as you like, but you’ll always be a tourist. No matter how hard you try, you’ll never see the real island, only beaches full of foreign holidaymakers and chintzy gift shops. You might get the occasional taste of it—a whiff of the exotic food the real islanders eat as you pass by, or a stolen glimpse of the real lives of the inhabitants over a whitewashed wall—but that’s all you’ll ever get.
In order to provide an adequate exposition of Harman’s noumenal cosmology, I shall divide my discussion of the split between the real and the sensual into three parts. I will first tackle the relation between the real and the sensual under the heading of withdrawal, which is the most famous aspect of Harman’s position. I will then show how this is complicated by the introduction of a second axis—the distinction between objects and qualities—under the heading of the fourfold, which is the name of the structure Harman derives from their intersection. Finally, I will address the most prominent metaphysical problem that emerges from Harman’s system, and his solution to it, which goes by the name of vicarious causation.