are intuitively the implementation of the grounding relation. In general, small-g
grounding relations induce big-G grounding, and this is why there is systematicity to
the array of grounding. To put it in slogan form, no small-g grounding between facts
without big-G grounding but no big G-grounding without some small-g grounding
as well. More carefully put, whenever big-G grounding is instantiated by some facts,
the transitive closure of the disjunction of the small-g grounding relations is also
instantiated.
Here is one potentially important difference between Wilson (2014) and me. In a
way, I have understressed the importance of“relative fundamentality”so far. In
addition to playing a direct role in the“real definition”of grounding, it plays an
indirect role in the characterization of what it is to be a small-g or suitable connecting
relation.^39 For me, what makes a given relation a small-g relation is that it is
uniformly correlated with a difference in the relative fundamentality of its relata,
i.e., R is a small-g relation if and only if necessarily, for allxandy,ifRxy, thenxis in
some way ontologically superior toy.^40 Accordingly, unlike Wilson (2014: 539), I do
not think of parthood as a small-g grounding relation, since some wholes are
ontologically superior to their parts and some parts are ontologically superior to
their wholes.^41 And certainly then numerical identity fails to be a small-g relation,
againpaceWilson (2014: 570–5).^42
What should we say about situations in whichxbears one small-g grounding
relation to ywhileybears a distinct small-g grounding relation tox? Perhaps
we should say that they are impossible.^43 That such situations are impossible is
(^39) Wilson (2014: 569) does suggest that whether a relation is a small-g relation will“typically depend”
on other facts, including which things are fundamental. 40
Alex Skiles has suggested to me that this criterion will count many gerrymandered relations as small-
g relations. For example, if set-membership is a small-g relation, then so too isx is a member of y and x is
such that 2 + 2 = 4. We could address this example by adding an additional necessary condition: R is a
small-g relation only if there is no other Rsuch that (i) Ris more natural than R and (ii) R*induces the
same pattern of ontological superiority as R. But probably the easier route is to accept that not all small-g
relations are of much interest to metaphysicians: only those that are sufficiently natural are. A related route
is to demand that a small-g relation be highly natural (but perhaps not perfectly natural!).“Highly natural”
is vague, and hence it might be vague what grounding is. I suspect that it is vague, and hence am not too
troubled by this consequence. For a contrary proposal to what I defend here, see Bennett (forthcoming),
who argues that patterns of relative fundamentality are a consequence of the distribution of what she calls
“building relations 41 ”; I hope to discuss Bennett’s intriguing view in future work.
For the same reason, I do not think that parthood is properly thought of as a“building”relation in the
distinctive sense that Bennett (2011b) gives to that expression. 42
It is also an open question whether I should accept thatdeterminationis a small-g grounding relation.
In section 2.2, I indicated that I thought that determinates of a property are equally natural as the
determinable of which they are determinates. In light of the results of chapter 7, I would now say that
determinates are as real as determinables. So being scarlet is as real as being red. But perhaps nonetheless
the fact thatxis scarlet is more real than the fact thatxis red. And if so, I could maintain that
determination is a small-g grounding relation. (Given that Wilson (2012) has similar views about the
nature of determinates and determinables, I am curious about whether she ought to think that determin-
ation is a small-g relation as well.) Thanks to Paek Chae-Young for discussion here. 43
In McDaniel (2009a), in the context of attempting to understand Armstrong’s (1997) version of
compositional pluralism, I distinguished between mereological composition and s-composition, the latter