Do wholes and their parts exist in different ways? The analytic establishment is hostile to modes of being, but its case is weak. Indeed some establishmentarians make no case at all; they simply bluster and asseverate and beg the question. I wonder how a member of the establishment would counter the following argument. Consider a house made of bricks and nothing but bricks, and let's list some pertinent truths and see what follows.
1. The house exists.
2. The bricks exist.
3. The house is composed of the bricks, all of them, and of nothing else, and is not something wholly distinct from them or in addition to them.
4. The bricks can exist without the house, but the house cannot exist without the bricks.
5. The relation between the house and the bricks is neither causal nor logical.
Therefore
6. The house has a dependent mode of existence unlike the bricks.
Peter van Inwagen, one of those establishmentarians who is hostile to the very idea of there being modes of being, will deny (1) as part of his general denial of artifacts. If artifacts do not exist at all, then questions about how they exist, or in what way or mode, obviously lapse. But it is evident to me that if we have to choose between denying artifacts and accepting modes of being, then we should accept modes of being!
(2) is undeniable as is (3): it would obviously be absurd to think of the house as something over and above its constituents, as if it could exist even if they didn't. The house is just the bricks arranged house-wise. This is consistent with the truth of (1). The fact that the house is just the bricks arranged house-wise does not entail that the house does not exist.
(4) is equally evident and is just a consequence of (3). I put the point modally but I could also make it temporally: before the Wise Pig assembled the bricks into a house fit to repel the huffing and puffing of the Big Bad Wolf, there was no house, but there were the bricks.
(5) is also obviously true. The bricks, taken individually or collectively, do not cause the house. Now an Aristotelian may want to speak of the bricks as the 'material cause' of the house, but that is not the issue. The issue is whether the bricks are the efficient cause of the cause. The answer to that is obviously in the negative. Nor are the bricks the cause of the house in the Humean sense of 'cause,' or in any modern sense of 'cause.' For one thing, causation is standardly taken to relate events and neither a house nor a set or sum of its constituents is an event.
Could we say that the relation between bricks and house is logical? No. Logical relations relate propositions and neither the bricks nor the house is a proposition. It is not a relation of supervenience either since supervenience relates properties and neither bricks nor house is a property.
But I hear an objection.
I agree with you that the house is not identical to the bricks and that the former depends on the latter but not vice versa. Why not just say that the two are related counterfactually? Had the bricks not existed, the house would not have existed either. Why not say that and be done with it? The house depends on the bricks but not conversely. But the dependence of one existent on another does not seem to require that there are different modes of existence.
True, had the bricks not existed, the house would not have existed. But what is the truth-maker of this counterfactual? Your objection is superficial. Obviously the house is not the bricks. Obviously the house is dependent on the bricks. I say that the house, as a whole of parts, exists-dependently. You said nothing that refutes this.
We should also ask whether it makes sense to speak of a relation between bricks and house. It is certainly not an external relation if an external relation is one whose holding is accidental to the existence of its terms. If brick A is on top of brick B, then they stand in a dyadic external relation: each can exist without standing in the relation, which is to say that their being related in this way is accidental to both of them. But a house and its bricks are not externally related: the house cannot exist apart from its 'relation' to the bricks.
The best thing to say here is that the house has a dependent mode of existence. The house exists and the bricks exist, but the house exists in a different way than the bricks do. If you deny this, then you are saying that the house and the bricks exist in the same way. And what way is that? Independently. But it is obvious that the house does not exist independently of the bricks.
I will end by suggesting that van Inwagen's strange denial of artifacts is motivated by his failure to appreciate that there are modes of being. For if there are no modes of being, and everything that exists exists in the same way, then one is forced to choose between saying either that the house exists independently of its constituent bricks or that the house does not exist at all. Since van Inwagen perceives that it is absurd to say that the house exists independently of its constituent bricks, he is forced to say that it does not exist at all.
But if there are modes of being we can maintain, rather more sensibly, both that the house exists and that it does not exist independently of its constituent bricks.
