 These suggestions are all quite tendentious. (1) is especially problematic since it rules out cases where the fact that \(F(x_1,\ldots,x_n)\) is grounded by the fact that \(F(y_1,\ldots,y_n)\): for example, one might want to say that the fact that Central Park is in New York City is partially grounded by the fact that Central Park is in Manhattan. While (2) avoids this problem, it is still hard to square with a thesis endorsed by most grounding theorists: that an existential generalization is partially grounded by each of its instances (Fine  2012,  59; Rosen  2010,  117). Consider a blob of clay \(x\) with a certain very specific shape-property \(S\). The thesis about existential generalizations entails that the fact that \(x\) has some shape or other is partially grounded by the fact that \(x\) has \(S\). But the idea that \(S\) is more natural than having some shape or other fits poorly with many other parts of the naturalness role, such as the connections to similarity, content, laws, and ampliative reasoning. A worry about (3) is that it might make it too hard for a property to count as perfectly natural. One might think that whenever the fact that \(F(x_1,\ldots,x_n)\) is ungrounded, there are also some other objects \(y_1,\ldots,y_n\) such that the fact that \(F(y_1,\ldots,y_n)\) is grounded: perhaps, for example, the ungrounded facts are all predications of mereologically simple objects of properties which are also instantiated by certain mereologically complex objects. Several of the generalizations also run into trouble if we assume a moderately coarse-grained conception of facts, on which (for example) the fact that Cleopatra loves Cleopatra is identical to the fact that Cleopatra is a self-lover. For example, under this assumption, (5) will have the surprising consequence that if the fact that \(R(x,x)\) is ungrounded, not only the binary relation \(R\), but also the monadic property bearing \(R\) to oneself is perfectly  natural.[67]  (Grounding-theorists often assume a fine-grained account of facts which would avoid this kind of problem; but there are worries about the consistency of such accounts similar to the worries about fine-grained theories of properties discussed in  §4.10.)  