It is commonly assumed that grounding relations are asymmetric. Here I develop and argue for a theory of metaphysical structure that takes grounding to be nonsymmetric rather than asymmetric. Even without infinite descending chains of dependence, it might be that every entity is grounded in some other entity. Having first addressed an immediate objection to the position under discussion, I introduce two examples of symmetric grounding. I give three arguments for the view that grounding is nonsymmetric (I call this view 'metaphysical interdependence'). These arguments are: (i) that metaphysical interdependence is the only theory able to reconcile competing intuitions about grounding; (ii) that it is the only theory consistent with both 'gunk' and 'junk'; and (iii) that offers a satisfactory solution to the problem concerning whether or not grounding is itself grounded.

Attempts to elucidate grounding are often made by connecting grounding to metaphysical explanation, but the notion of metaphysical explanation is itself opaque, and has received little attention in the literature. We can appeal to theories of explanation in the philosophy of science to give us a characterisation of metaphysical explanation, but this reveals a tension between three theses: that grounding relations are objective and mind-independent; that there are pragmatic elements to metaphysical explanation; and that grounding and metaphysical explanation share a close connection. Holding fixed the mind-independence of grounding, I show that neither horn of the resultant dilemma can be blunted. Consequently, we should reject the assumption that grounding relations are mind-independent.

Grounding talk has become increasingly familiar in contemporary philosophical discussion. Most discussants of grounding think that grounding talk is useful, intelligible, and accurately describes metaphysical reality. Call them realists about grounding. Some dissenters reject grounding talk on the grounds that it is unintelligible, or unmotivated. They would prefer to eliminate grounding talk from philosophy, so we can call them eliminitivists about grounding. This paper outlines a new position in the debate about grounding, defending the view that grounding talk is (or at least can be) intelligible and useful. Grounding talk does not, however, provide a literal and veridical description of mind-independent metaphysical reality. This (non-eliminative) irrealism about grounding treads a path between realism and eliminativism.

This paper argues for an alternative to orthodox foundationalist accounts of metaphysical structure as characterized by grounding relations. There are good reasons to take grounding to be a non-symmetric (rather than an asymmetric) relation, and to take facts to be related in complex networks of ground. These networks are closely analogous to the networks of justified beliefs characteristic of coherentism about justification. This position is called metaphysical interdependence. The chapter argues that grounding is an explanatory relation (rather than merely a relation which backs explanations), and that there are good reasons to resist the contention that explanation is asymmetric, including cases seemingly best described as cases of holistic metaphysical explanation. Metaphysical interdependence is a promising account of the metaphysical structure of reality.

This paper develops an account of metaphysical explanation according to which metaphysical explanations are answers to what-makes-it-the-case-that questions. On this view, metaphysical explanations are not to be considered entirely objective, but are subject to epistemic constraints imposed by the context in which a relevant question is asked. The resultant account of metaphysical explanation is developed independently of any particular views about grounding. Toward the end of the paper an application of the view is proposed that takes metaphysical explanations conceived in this way to characterize reality's structure. According to this proposal, reality's structure is partly constituted by a projection of our explanatory practices onto reality.