© Philosophy Today, Volume 63, Issue 1 (Winter 2019). ISSN 0031-8256 101–124 DOI: 10.5840/philtoday2019611259 Excessive Materialism and the Metaphysical Basis for an Object-Oriented Ethics JUSTIN L. HARMON Abstract: Te aims of this paper are twofold: (1) to critique Graham Harman’s avowedly nonrelational object-oriented ontology from the shared relational vantage of ethics, social philosophy, and feminist new materialism; and (2) to articulate the metaphysical basis for a materialist ontology that serves at once as a posthumanist metaethic, or, as I call it, proto-ethic. Te nascent movements of speculative realism and object-oriented ontology suggest some fruitful strategies for challenging the an- thropocentrism of the post-Kantian philosophical landscape. Tey do so, however, by simultaneously foreclosing the possibility of thinking with these strategies to address moral and political problems, insofar as they characterize the real as fundamentally nonrelational. I argue that Harman’s adopted noumenalism is ultimately self-un- dermining, and ofer as an alternative a materialist account of reality as intrinsically phenomenal, where phenomenality is unpacked as the excessive, ongoing source of proto-ethical norms to which every human ethical system implicitly appeals. Key words: posthumanism, ethics, materialism, object-oriented ontology, specula- tive realism Tese things we call matter, the life-motes, or the seeds of things, (if we must fnd, in schools, a name for them). —Lucretius (De Rerum Natura, Book I) I n this paper I defend a version of materialist ontology as a legitimate avenue to metaphysical realism against its reductive dismissal by leading proponents of object-oriented philosophy (OOP). It is, however, in the