«Consider water. Why does it contain hydrogen? One permissible answer is this: water by its very nature contains hydrogen. Or consider Socrates’ ...»
Draft of February 2016
Consider water. Why does it contain hydrogen? One permissible answer
is this: water by its very nature contains hydrogen. Or consider Socrates’
singleton set. Why does this set have Socrates as a member? It has
Socrates as a member by its very nature.
Let us call such explanations essentialist explanations. In an essentialist explanation, we explain the fact that A in terms of the fact that
a certain thing is by its very nature such that A (or, as I will often say, is essentially such that A).1,2 We may think of the claim that a thing is essentially a certain way as a partial statement of what the thing is ‘at its core’.3 Thus part of what water is at its core, for example, is a compound containing hydrogen. I take it that whenever something is essentially such that A, the fact that A will admit of this kind of explanation.
Essentialist explanation is ubiquitous in philosophy. For example, we can explain why what is known must be true by saying that the nature of knowledge is such that what is known must be true. Or again, a functionalist about the mind may think that we can explain why pain plays a certain causal role by saying that pain plays this role by its very nature. Again, a defender of John Rawls’s view of justice may think we can explain why a just society will eliminate inequalities not reasonably expected to work out for everyone’s advantage by saying that the nature I will use these essentialist locutions (and obvious variations on them) interchangeably. Nothing will turn on any differences in logical form between such locutions.
I will take facts (and propositions) to be structured entities built up from worldly constituents like objects, properties, operations and so on. The fact that A will therefore be distinct from the fact that t is essentially such that A.
Fine (1995b) distinguishes a number of notions of essence. In this paper I have in mind something very close to Fine’s notion of immediate constitutive essence, though I am not sure he thinks of such essence as what something is at its core. For further discussion of essence see Fine (1994), Correia (2006) and Koslicki (2011), among others.
of justice is such that a just society will eliminate such inequalities.4 A remarkable feature of essentialist explanation is what we may call its ultimacy. Suppose we ask why singleton Socrates contains Socrates, and suppose we answer by saying that it is in the very nature of this set to contain Socrates. One then has the sense that this is ‘the end of the explanatory road’. With apologies to Wittgenstein, we have here reached bedrock and our spade is turned. We are inclined to say: ‘This is simply what this set is.’5 The aim of this paper is to clarify the notion of essentialist explanation and the sense in which such explanation is ultimate. I begin by distinguishing essentialist explanation from some related kinds of explanation (§1). There has recently been some interest in the proposal that essentialist explanation should be understood in terms of the notion of ground; I argue against this proposal (§2). I then turn to the ultimacy of essentialist explanation. I give an account of this ultimacy (§3). Not only is this account natural, it is supported by an independently plausible principle that I call the inessentiality of essence (§4). I close by suggesting that the inessentiality of essence is the key to understanding why essentialist explanations are so satisfying (§5).
1 Distinguishing essentialist explanation Let us say that an essentialist fact is a fact of the form ‘t is by its nature such that A’ (or of the form ‘t is essentially such that A’).6 Not every explanation which appeals to an essentialist fact is an essentialist explanation in our sense. For even if an explanation appeals to an essentialist fact, it will not be an essentialist explanation if it is not of the form ‘A because t is essentially such that A’. It is important to distinguish these from essentialist explanations since they do not in general share such explanations’ ultimacy.
For an example of an explanation which appeals to an essentialist fact but which is not an essentialist explanation, consider the fact that a Rawls (1958).
Wittgenstein (1953, §217).
One might think that in addition to such ‘individual’ essentialist facts there are ‘collective’ essentialist facts. The appendix generalizes the arguments of this paper to the collective case.
certain parking lot is square in shape. One might think we can explain this fact by saying that the lot is equilaterally rectangular and that it is in the nature of being square that whatever is equilaterally rectangular is also square. This explanation appeals to an essentialist fact but is not of the proper form to be an essentialist explanation.7 Nor should we think that any explanation which appeals only to an essentialist fact will be an essentialist explanation. Consider, for instance, the disjunctive fact that either snow is green or 3 is essentially a number.
One might think that this fact can be explained solely by appeal to the fact that 3 is essentially a number. But even if this is so, the explanation is not of the proper form to be an essentialist explanation.
We should also distinguish essentialist explanations from ‘hybrid’ explanations, obtainable by chaining an essentialist explanation with an explanation of some other kind. Consider, for example, the fact that saltpeter dissolves in water. One might think this fact can be explained by saying that nitrate salts dissolve in water and that saltpeter is by its very nature a nitrate salt. This explanation is again not of the proper form to be an essentialist explanation. But it may be regarded as a hybrid explanation, obtainable by chaining an essentialist explanation with a causal explanation in the following way. We ﬁrst give a causal explanation of the fact that saltpeter dissolves in water by saying that it is a nitrate salt and that such salts dissolve in water. We then give an essentialist explanation of the fact that saltpeter is a nitrate salt by saying that it is so by its very nature.
2 Essentialist explanation and ground Faced with the phenomenon of essentialist explanation, it is natural to want to see it as a species of some other kind of explanation. But I will argue that this cannot be done.
Essentialist explanation is clearly not a species of causal explanation.
Causal explanation, after all, proceeds by identifying causes. But water’s containing hydrogen, for instance, is not caused by its essentially containing hydrogen.
I leave aside the question of how such explanations should be understood, though see Kment (2014) for discussion.
Might essentialist explanation instead be a species of grounding explanation? There has recently been some interest in this proposal.8 In a grounding explanation, we explain a fact by saying what grounds it, or by saying what the fact consists in.9,10 Thus we might explain why a given thing is red by saying that it is crimson. Or we might explain why it is rainy or windy by saying that it is rainy. Or again, we might explain why it is true that snow is white by saying that snow is white. According to this proposal, an essentialist explanation is just a grounding explanation whose explanandum is of the form ‘A’ and whose explanans is of the form ‘t is essentially such that A’. Thus water’s containing hydrogen will be explained by its essentially containing hydrogen in much the same way that a given thing’s being red is explained by its being crimson.
The philosophers who have been interested in this proposal have not given sustained arguments for it. Their thinking has seemed to be that since ‘t is essentially such that A’ provides a metaphysical kind of explanation of A and since grounding explanation is the only metaphysical kind of explanation, this explanation must be a grounding explanation. Although the notion of a metaphysical kind of explanation is not perfectly clear, the intuitive idea is that a metaphysical kind of explanation is one that pertains to the distinctive concerns of metaphysics. The exact characterization of this notion need not detain us since our appeals to it will be uncontroversial enough. Grounding explanation, for instance, will be a metaphysical kind of explanation, while causal explanation will not be.
It can hardly be denied that ‘t is essentially such that A’ provides a metaphysical kind of explanation of A. But metaphysicians’ recent enthusiasm over ground notwithstanding, it is not clear that grounding explanation is the only metaphysical kind of explanation. Certainly this should not simply be assumed without argument. I therefore do not think these philosophers have established that essentialist explanation is a species of Rosen (2010) ﬂirts with the proposal, Dasgupta (2014a, §5) apparently presupposes it and Kment (2014) explicitly endorses it.
For discussion of ground and grounding explanation, see Fine (2001, 2012a), Schaffer (2009) and Rosen (2010), among others. The proposal (as well as the grounding account of ultimacy rejected in §3) presupposes a uniﬁed notion of ground. This presupposition has been challenged by Wilson (2014) and Koslicki (2015); so much the worse for my opponent if they are right.
One may distinguish notions of full and partial grounding explanation. Since an essentialist explanation is clearly a full explanation, the proposal is plausible only if understood as involving full grounding explanation.
grounding explanation.11 Indeed, even before considering detailed arguments against this proposal we can see that it is open to signiﬁcant doubt. For it is not at all clear that the fact that water contains hydrogen, for instance, is grounded in the fact that water essentially contains hydrogen. After all, it is not at all clear that water’s containing hydrogen consists in its essentially containing hydrogen, in the way that something’s being red consists in its being crimson. And yet if essentialist explanation is a species of grounding explanation then this must be so.
These doubts are substantiated by the following argument against the proposal. It is not implausible to think that what is in the nature of a given thing can lack grounds altogether. To see this, consider the many metaphysicians who defer to science in their metaphysical speculation. Where the deliverances of science are clear, they will ‘read off’ their metaphysics from these. For instance, if there is a scientiﬁc reduction of thermodynamics to statistical mechanics, they will take thermodynamic facts to be grounded in statistical mechanical facts. But where science is silent, they will feel free to speculate.
Suppose such a metaphysician comes to consider the fact that a certain electron has unit negative charge. What might she say about this fact? Her sense of the science may well incline her to take it to be a ‘rock-bottom’ fact about reality. She may well think, that is, that it is not grounded in any other fact. But what might she say about the electron’s essence? She may well take science to be silent on the matter and so feel free to speculate. She may hold, for instance, that the electron essentially has unit negative charge. The fact that the electron has unit negative charge will then have an essentialist explanation in terms of this essentialist fact. But if the former is not grounded in any other fact, it is a fortiori not grounded in this essentialist fact. This scientiﬁcially-deferent metaphysician will thus countenance an essentialist explanation where no grounding explanation exists. And so essentialist explanation cannot One might, of course, use ‘grounding explanation’ simply to refer to any explanation of a metaphysical kind. But philosophers working on grounding explanation have tended instead to characterize such explanation by reference to paradigm cases, such as the explanation of a conjunctive fact in terms of its conjuncts, of a disjunctive fact in terms of its true disjuncts, of the possession of a determinable property in terms of the possession of a determinate property, and so on. I will follow this approach here.
be a species of grounding explanation.