In each of 1.3.1-1.3.3, I have identified a problematic epistemic or semantic assump- tion traditionally associated with regulative arguments. In each case, I have argued that the assumption is inessential. We can summarize the above discussion with the following key points:
1. Our interests and concerns in ordinary life are different from our interests and concerns when doing philosophy (see 1.2.2).
2. Because of (1), the ordinary epistemology of our judgments can neither be threatened nor vindicated by philosophical argument (see 1.3.1 and 1.3.2). 3. Because of (1), there is no need for a philosophical theory explaining the ordinary epistemology of our judgments (see 1.3.3).
Stripped of their problematic assumptions, I think that regulative arguments should have an important role in contemporary metaphysics.
1.4 Contemporary applications
In this section, I’ll briefly describe some of the targets of the regulative arguments developed in my dissertation. This section will summarize and draw from the main results of the chapters ahead.
1.4.1 Causation (ch. 2)
We think that some things have a unified nature for us to discover.21 For example, we think science has revealed the nature of water to be H2O. We think that other things do not
have a unified nature for us to discover. For example, we do not think that there is anything to discover about what it is to be a game.
What about the causal relation, or dispositions, or free will? For any philosophically- interesting itemX, one can find a host of competing theories regarding the nature ofX. In offering such analyses, philosophers assume thatXis relevantly similar to water, not game- hood. My project in chapter 2 is to show how, in a given particular case, this assumption might be challenged.
I begin by identifying a semantic difference between terms like ‘water’ and terms like ‘game’ that explains why an informative analysis is possible for the former but not the latter.22 This difference can be seen by comparing two thought experiments.
Suppose that all of our ordinary evidence suggests that a certain sampleX is water: it has the right appearance, taste, boiling point, etc. On the basis of this evidence, we would justifiably endorse the sentenceP ≡‘Xis a sample of water’. But notice thatP is hostage to empirical fortune: if we were to find out thatX has a different chemical structure from the one shared by all the other water-like liquids in our environment, we would revise our judgment and conclude thatP is false. This shows thatP’s truth presupposes thatXshares
21I precisify what I mean by a “discoverable, unified nature” in chapter 2.
22I actually identify two semantic differences, but for ease of presentation, I will describe only one of
some unified nature with other water-like substances in our environment.
But the following thought experiment shows that game judgments are different.23 Sup- pose we become convinced that a certain theoryAis the best possible analysis of gamehood (on whatever desiderata for theory choice one prefers24). But suppose (plausibly enough)
that there are stillsome cases whereAconflicts with our intuitions; for example, perhaps A classifies multiplication tables as games. Now consider: how would our belief that A is the best possible analysis of gamehood affect the game-judgments we are disposed to make inordinary contexts? For example, how would it affect our disposition to assertQ≡
‘Multiplication tables are not games’ in ordinary contexts? I submit that, even if we were convinced that Awas the best possible analysis of gamehood, we would feel no pressure at all to revise our judgment thatQ(in any ordinary context). We would continue to assert Qjust as we always had. This is because, when judging whetherY is a game in ordinary contexts, we do notcarewhether it shares some unifying feature with other cases of games. This thought experiment reveals an important difference between ‘water’ and ‘game’. The fact that we revise our water-judgments when we learn that X does not share some unifying feature with other water-like samples suggests that ‘water’ expresses a property with a unified nature. But the fact that we feel no similar pressure to revise our game- judgments suggests that ‘game’ does not express a property with a unified nature. To capture this difference, I will say that game judgments are epistemically secure in a way that water judgments are not: our judgment that X is a game is not threatened by the possibility thatXfails to share some unifying feature with other games.
The above discussion provides a method for determining whether a philosophically- interesting item X can be given an informative analysis: we test whether X-judgments are epistemically secure in the way described above. To illustrate this method, I consider
23While this thought experiment does not directly appeal to an Oracle (see 1.3.1), it has a very similar
structure and purpose.
24For example, perhaps we become convinced thatAupholds more of our our intuitive judgments than
causal judgments, ultimately defending the following thesis:
Thesis: The term ‘cause’ does not have the semantic role of expressing a rela- tion with a discoverable, unified nature
1.4.2 Existence (ch. 3)
There is a vigorous debate over the existence of material objects like tables and trees. But deflationary theorists like Thomasson (2007) and Hirsch (2011) have argued that there is something misguided about this debate. It seems that, in ordinary language, the sen- tence ‘The table exists’ has the status of a trivial truth (on the assumption that there are particles arranged table-wise). So deflationists claim that the composition debate can be trivially resolved in favor of realism simply by reflecting on how we use ordinary English. Deflationists have made similar claims about other areas of ontology as well.25
Recently, some ontologists have claimed that there can still be substantive debates in ontology even if deflationists are correct about ordinary language.26 The claim is that, even if it is trivially true in ordinary English that tables exist, there is still a substantive debate over whether tablesexist*, where the existence* quantifier is a quantifier stipulated to correspond to the world’s most natural carving. Following Sider (2014), we can call the proposed shift in quantifiers theOntologese gambit.
Some deflationists have worried that the notion of an existence* quantifier is unintel- ligible.27 But in this chapter, I will raise an independent objection. I will argue that, even if we grant thatsomeexistence* questions are substantive, there are no substantive questions to ask about the existence* of things like ordinary objects, numbers, and properties – things whose ordinaryexistence is given a deflationary treatment. More precisely, I defend the following thesis:
25For example, Schiffer (2003, 2.3) argues that we can trivially establish the existence of properties by
looking to the ordinary use of property terms.
26See, e.g., Cameron (2010). 27See Hirsch (2011, 195).
Thesis: If the deflationist offers the correct explanation of the triviality of a certainordinary existence statement, then there is no substantive question to ask about the truth of the corresponding existence statement
To defend this conclusion, I appeal to scrutability results (see 1.3.1) involving our ordinary object discourse.
1.4.3 Laws of nature (ch. 4)
Many philosophers have worried about the epistemology of non-Humean laws.28 It is
clear how we learn about the Humean base; at least in many cases, we directly observe and measure it. But if the laws are something over and above the Humean base, it is not clear how we could ever be epistemically justified in our beliefs about the laws.
The above argument has the form of a traditional regulative argument (see 1.2.1). But it is inconclusive as it stands. Along the lines of 1.3.2, non-Humeans have claimed that justified belief in the laws is possible even on the non-Humean view. For example, some non-Humeans have claimed that we are justified in positing non-Humean laws because they are needed to explain the striking empirical regularities science has discovered.29
In chapter 4, I give an updated regulative argument for Humean laws which evades this non-Humean response:
Updated Regulative Argument for Humeanism
Premise 1: Even if scientists were to receive evidence E that — by the non- Humean’s lights — falsifies their law judgments, they would not alter their law discourse.
Premise 2: If scientists would not alter their law discourse upon learningE, scientists are not referring to non-Humean laws when they use the term ‘law’ in ordinary scientific contexts.
3: Scientists are not referring to non-Humean laws when they use the term
28See, e.g., Earman & Roberts (2005). 29See, e.g., Armstrong (1983, 52-59).
‘law’ in ordinary scientific contexts. (from 1,2)
Corollary: two possible worlds cannot differ on what is a law of nature unless they also differ in their Humean base.
To establish premise 1, I consider Oracle thought experiments (see 3.1.2) where the Oracle tells us that the non-Humean laws are different than what ordinary scientific evi- dence leads us to believe. I argue that scientists would not change their law discourse in response to this testimony because of the central role that the law/non-law distinction has within ordinary scientific practice.
1.4.4 Dependence (ch. 5)
Some theorists (e.g., Schaffer (2009)) have recently claimed that the world has an or- dered, hierarchical structure. Entities at lower ontological levels are said tometaphysically groundentities at higher ontological levels. In general, theorists claim that we need meta- physical grounding in order to accommodate cases of non-causal explanation:30
1. xis roughly spherical in virtue of its having determinate shapeR. 2. xis fragile in virtue of its molecular arrangement and the physical laws.
3. x’s action is wrong in virtue of its being done with the sole motive to cause harm.
It is said, for example, that the fact x’s being roughly spherical is metaphysically grounded by the factx’s having a determinate shape R. But in chapter 5, I argue that there is another way to understand cases of non-causal explanation. Consider the following ex- amples:
10. xis a vixen in virtue of the fact thatxis a female fox. 20. xis a piece of furniture in virtue of fact thatxis a chair.
30. xis bald in virtue of the fact thatxhas 20 hairs.
In cases [10]-[30], the relevant explanation seems to be conceptual rather than meta- physical. We can say that these cases involve conceptual grounding, where conceptual grounding is a semantic relation between our sentences rather than a metaphysical connec- tion between things out in the world. Intuitively,Sconceptually groundsT if the sentence ‘IfS, thenT’ is true because of the constitutive inferential roles of the expressions inSand T (see 1.3.3).
My project in chapter 5 is to clarify the relation between these two types of grounding. I argue that conceptual and metaphysical grounding are exclusive: if a given in-virtue-of claim involves conceptual grounding, then it does not involve metaphysical grounding.
Here is one such argument for grounding exclusion. Suppose we consider a case like [1], which features the property being roughly spherical. There are various views one might take of this property. One option is to say thatbeing roughly sphericaldoesn’t exist (eliminativism). Another option is to identify it with a set or a predicate (nominalism). Another option is to view it as a deflationary entity: a mere “shadow of a predicate”.31 Or one can adopt a “heavyweight” view of this property, which I use as a catch-all term for any view not canvased above.
In chapter 5, I first argue that anyone who views [1] as a case of metaphysical ground- ing is implicitly committed to viewing the property being roughly spherical as heavy- weight. Next, I argue that we cannot trivially infer that any given heavyweight property is instantiated. But now suppose that [1] involves conceptual grounding. Then the infer- ence between the sentences ‘xhas determinate shapeR’ and ‘xis roughly spherical’will be trivial for ordinary subjects. So I use this scrutability result in a regulative argument to establish that the propertybeing roughly sphericalis not heavyweight.32 This entails that
31See Schiffer (2003).
[1] does not involve metaphysical grounding.
I argue that the same considerations apply to many other proposed cases of meta- physical grounding. Once we recognize that these cases involve semantic connections, we cannot view the relevant objects and properties in the heavyweight way that is needed to view the case as involving metaphysical grounding.
1.4.5 Edenic Idealism (chs. 6-11)
Science suggests that the “external world” is very different from the world presented to us in experience. For example, most theorists today reject the claim that external objects have the vivid, sensuous color properties that they seem to have in experience. For a second example: results from special and general relativity suggest that external space is very different from the space presented to us in experience.
Despite these results, most philosophers think that we can uphold the truth of our everyday judgments about ordinary objects through a strategy calledfunctional identifica- tion. The basic idea is: even if the world does not contain vivid, sensuous redness, the world does contain properties (such as surface reflectance properties and dispositional properties) whose role is similar enough to preserve our ordinary usage. By saying that ‘redness’ refers to one of those properties, we can preserve the truth of our ordinary color judgments.33
But in chapter 6, I present a series of puzzles for this standard strategy. The puzzles are cases where it is very difficult to match up the objects and properties presented in experience with corresponding items in the external world.
On first pass, we might be tempted to say that the puzzles are cases where ordinary objects don’t exist. But I use an Oracle argument like the one given in the introduction to show that this conclusion is mistaken. On the basis of this Oracle argument, I offer the following regulative argument (see 1.3.1) against realism about ordinary objects:
33Tye (2000) and McLaughlin (2003) adopt this strategy for colors, while Thompson (2010) and Chalmers
Updated regulative argument against realism
Premise 1: Even if ordinary subjects were to learn that the external world WE does not contain suitable denotations for their ordinary object terms,
they would not alter their discourse about objects.
Premise 2: If ordinary subjects would not alter their object discourse upon learning thatWE has no suitable denotations for their object terms, terms
like ‘table’ and ‘chair’ do not have the semantic role of referring to items fromWE.
3. Terms like ‘table’ and ‘chair’ do not have the semantic role of referring to items fromWE.34.
Supposing this argument is successful, what doour ordinary object terms refer to? I argue that the best way to explain the our response to the Oracle’s testimony is to adopt the following semantic form of idealism:
Edenic Idealism (EI): Ordinary object terms refer to items in the manifest world: the world WM of primitive objects and properties presented by our
experiences.
For example, suppose you have a phenomenal experience of an apple. The realist wants to identify this apple with some item in the external world. But according to edenic idealism, the apple is a denizen of the possible world WM presented by your experience.
Far from being some outlandish metaphysical theory, I argue that, in fact, EI is the position of common sense. It is the most intuitively plausible view about what we are actually talking about when we use terms for ordinary objects.
In chapter 7, I develop the edenic idealist’s positive metaphysical account in more detail. In chapters 8-10, I defend edenic idealism from various traditional objections to idealism. I conclude by discussing some applications of edenic idealism in chapter 11.