Hinge Propositions, Skeptical Dogmatism, and External World Disjunctivism

Dr. Mark WalkerNew Mexico State University mwalker@nmsu.edu

Abstract

Following Wittgenstein’s lead, Crispin Wright and others have argued that hinge propositions are

immune from skeptical doubt. In particular, the entitlement strategy, as we shall refer to it, says that hinge

propositions have a special type of justification (entitlement justification) because of their role in our

cognitive lives. Two major criticisms are raised here against the entitlement strategy when used in attempts

to justify belief in the external world. First, the hinge strategy is not sufficient to thwart underdetermination

skepticism, since underdetermination considerations lead to a much stronger form of skepticism than is

commonly realized. Second, the claim that hinge propositions are necessary to trust perception is false.

There is an alternative to endorsing a particular hinge proposition about the external world, external

world disjunctivism, which permits us to trust perception (to a point), while skirting the difficulties raised

by skepticism.

Keywords: hinge proposition, skepticism, external world, underdetermination, Crispin Wright, skeptical dogmatism

Introductory

One deployment of Wittgenstein’s notion of hinge propositions, specifically what we shall refer to as the

‘entitlement strategy’ as championed by Crispin Wright and others, is said to offer an antidote to some

forms of skepticism.1 As we shall see, the basic anti-skeptical thrust of the entitlement strategy is the claim

that skepticism depends on too narrow a conception of ‘justification’: Skeptics fail to realize that hinge

1 The idea of hinge propositions comes, of course, from Wittgenstein’s On Certainty: “…the questions that we raise and

our doubts depend upon the fact that some propositions are exempt from doubt, are as it were like hinges on which those turn.”

(2009, 376). As is often noted, On Certainty is incomplete and fragmentary in many respects, which has led to a number of

different developments of Wittgenstein’s ideas. See Pritchard (2005) for more on this point. For a good overview of some of the

interpretative issues, see McGinn (2008) and Coliva (2010a, 2015).1

propositions are epistemically justified in terms of their importance in serving epistemic goals other than

evidential concerns.

I will argue on two fronts against the entitlement strategy as an antidote to skepticism about the

external world based on underdetermination considerations.2 First, the entitlement strategy is not sufficient

to thwart skeptical underdetermination considerations, since underdetermination considerations lead to a

much stronger form of skepticism than is commonly realized. Second, the claim that hinge propositions are

necessary to trust perception is false. In particular, it will be shown there is an alternative, a view I shall

refer to as ‘external world disjunctionism’, which permits us to trust perception (to a point), while skirting

the difficulties raised by skepticism.3 We will begin with a look at underdetermination skepticism and the

entitlement strategy in the next couple of sections before turning to the two criticisms of the entitlement

strategy.

The External World and Underdetermination Skepticism

It will help to begin with a clarification of the term ‘external world’. If ‘external world’ means ‘something

other than me’, then strictly speaking, any number of skeptical hypotheses may qualify as an ‘external

world’. For example, Berkeley’s immaterial world and Descartes’ evil demon world count as ‘external to

me’. We will reserve the term ‘external world’ for this rather vague sense of ‘something other than me’ and

use ‘Mundane World Hypothesis’ (hereafter ‘1MWH’) to refer to the more specific sense of ‘external

world’ that many have in mind:

1MWH: (i) We have bodies, (ii) we have brains located inside our bodies, (iii) and we have sense

organs which process visual information. (iv) The direct cause of our perceptual judgments is

typically macroscopic material objects (tables, trees, teacups, etc.), and (v) we live in a material

world. In addition, (vi) our epistemic relationship to the world is autonomous: evil demons,

advanced aliens, and so on, do not get involved in our epistemic lives (Walker, 2015).

2 I should add that the present argument does imply that the entitlement strategy is ineffective in all domains. For all that is said

here, the entitlement strategy may, for example, supply an antidote to skepticism about mathematical truths, induction, or logical

laws even if it fails to answer skepticism about the external world. See, for example, Wright (2004a).

3 In section 8, I briefly discuss the difference between disjunctionism and disjunctivism, where I suggest that they are quite

different responses to the problem of skepticism. 2

Underdetermination skeptics ask us to consider a competitor to 1MWH, like The Matrix World Hypothesis:

2MtWH: I am in ‘The Matrix.’ I live in a virtual reality maintained by a computer system that

interfaces with my brain. The computer system is controlled by advanced Artificial Intelligences

(AIs) who have taken control of the world.

2MtWH denies (iv), proposing instead that a computer program (The Matrix) is the typical cause of our

experience. 2MtWH also denies (vi) by claiming that our lives in the virtual world are orchestrated by

agents (AIs) controlling the Matrix. Thus, the 1MWH explanation for why it appears there is a desk in front

of me is that there is a material desk in front of me that reflects light to my eyes, which is processed by my

brain to produce a visual image of a desk. 2MtWH says that electrodes feed minute electrical impulses into

nerve endings in my brain, producing an experience that is subjectively indistinguishable from seeing a

material desk. The electrical impulses are controlled by a computer program designed to realistically

simulate a three-dimensional world of material objects. The explanation for the appearance of a desk is

something like a ‘desk file’ that is designed to simulate a material desk to all inhabitants of the virtual

world. Such hypotheses we will term ‘metaphysical’ in the sense that they are said to explain appearances.

A word of clarification about the disputants about the justificatory status of 1MWH and other

metaphysical hypotheses is also in order. ‘Skeptics’, as we will understand the position, maintain that

hypotheses like 1MWH are not justified. There is less agreement about the name for the skeptic’s usual

opponent. Following the ancients, we will use the term ‘dogmatist’ to designate those who we believe have

justified belief about some subject matter.4 In the present case, then, a dogmatist about 1MWH is someone

who believes we have justified belief about 1MWH. Most philosophers, and indeed most humans, are

dogmatists in this non-pejorative sense.

Underdetermination skeptics challenge dogmatists to cite evidence that favors 1MWH over

2MtWH. They argue that any such evidence would have to be either a priori or empirical and add:

(I) We have no empirical access to the nature of the cause of our sensory experience that favors

1MWH, since subjectively, our experience would be indistinguishable if 2MtWH were true. That is,

4 Hence, the usage is close to that of Sextus Empiricus. See Mates (1996, 1.1-3).3

if the cause of our sensory experience is 2MtWH, it would be subjectively indistinguishable from

the counterfactual possibility that 1MWH is the cause of our sensory experience, and, if the cause of

our sensory experience is 1MWH, it would be subjectively indistinguishable from the

counterfactual possibility that 2MtWH is the cause of our sensory experience.

(II) We have no a priori access to the nature of the causes of our experiences which favor 1MWH over

2MtWH.

The underdetermination skeptic concludes that we are not justified in believing 1MWH because it has no

more going for it, evidentially speaking, than 2MtWH.

We may summarize the structure of the underdetermination argument (UA) for skepticism about the

1MWH thus:

UP: If h1 and h2 are incompatible hypotheses and e is all S’s evidence, then S is justified in

believing h1 only if Pr(h1/e) > Pr(h2/e).5

UM: It is not the case that Pr(1MWH/e) > Pr(2MtWH/e) for these incompatible hypotheses.

UC: We are not justified in believing in 1MWH.

The major premise, UP, states one version of the underdetermination principle where ‘Pr’ stands for

‘epistemic probability’. UP states this necessary condition for justified belief: a justified belief about some

hypothesis must have greater epistemic probability than its competitor.

The skeptic’s defense of the minor premise (UM) was outlined above: skeptics claim (I) sensory

evidence does not favor 1MWH over some skeptical competitor, and (II) we have no a priori evidence that

favors 1MWH over its incompatible skeptical competitor.

The Entitlement Strategy

This brief rehearsal of the familiar underdetermination argument should be enough for us to understand the

entitlement strategy’s main counterclaim: underdetermination skepticism focuses only on justification

5 There are different formulations of UP in the literature. This formulation is mostly borrowed from Hazlett (2006, 200). See

Walker (2016b) for some discussion of different versions of the principle.4

understood as an evidentiary notion. According to the entitlement strategy, hinge propositions may enjoy a

different type of justification.6 Crispin Wright writes:

Suppose there is a type of [justification] which one does not have to do any specific

evidential work to earn: better, a type of [justification] whose possession does not require the

existence of evidence in the broadest sense encompassing both a priori and empirical

considerations for the truth of the [justified] proposition.  Call it entitlement.  If I am entitled

to accept P, then my doing so is beyond rational reproach even though I can point to no

cognitive accomplishment in my life, whether empirical or a priori, inferential or non-

inferential, whose upshot could reasonably be contended to be that I had come to know that

P, or had succeeded in getting evidence justifying P (2004b, 174-175). 7

To clarify further, let us distinguish between ‘evidential justification’ and ‘entitlement justification’. The

usual sense of ‘justification’, as Wright indicates, involves empirical or a priori considerations in support of

some proposition. ‘Entitlement justification’ is the type of justification for propositions that serve the

epistemic goal of having lots of knowledge. Allan Hazlett’s example of ‘Liars’ nicely illustrates the point:

“I learn that 50% of people are terrible liars, that they lie almost all the time, and about the most mundane

things, and that I’m not that different from everyone else. I’m justified in believing this, and am in spite of

this justified in trusting testimony” (2006, 205).8 As Hazlett notes, there may be several senses in which

one is justified in trusting testimony. One might be morally justified or pragmatically justified. For

example, the goal of getting along with others might require that one trusts the testimony of others.

6 I’ll discuss competing conceptions of ‘hinge proposition’ at the end of this section.

7 I have replaced ‘rational warrant’ with ‘justification’ in Wright’s quote in order to keep terms straight. Wright uses ‘warrant’ to

encompass the disjunction of what we will call below ‘entitlement justification’ and ‘evidential justification’ where we will use

simply ‘justification’. Wright’s understanding of ‘justification’ encompasses just evidential justification.

8 While there are some differences in the way they draw the distinction between evidential and entitlement justification, for our

purposes, two similarities are most important: (i) Evidential justification is not the only form of epistemic justification, and (ii)

both invoke a defeater condition (discussed below). One difference between Wright and Hazlett is that Hazlett’s discussion

seems to lean more to what I describe below (footnote ??24) as the teleological interpretation of entitlement. 5

However, trusting testimony also serves a specific epistemic goal: the goal of having lots of knowledge.

For example, suppose I claim to know that China is the most populous country in the world. How do I

know this? Not by reasoning a priori about the concept of China, and not through my own empirical

observation—I’ve never been to China. The answer, of course, is by testimony. If I did not trust testimony,

then I would lose such knowledge.

The connection with hinge propositions is spelt out by Hazlett as follows, “If one failed to believe

in the external world, one would be forced, if rational, to distrust perception at the very least…” (2006,

205). What Hazlett means by ‘external world’ appears to be pretty much what is meant by ‘1MWH’. We

may summarize the response to the skeptic by saying that the entitlement strategy suggests that the

evidential justification for 1MWH does not exhaust the justification for 1MWH. 1MWH also has

entitlement justification because of the role of 1MWH in trusting perception as a source of knowledge.

It is important to note that with respect to skepticism, the entitlement strategy is concessive. As

Wright observes:

This line of reply concedes that the best sceptical arguments have something to teach us—

that the limits of [evidential] justification they bring out are genuine and essential—but then

replies that, just for that reason, cognitive achievement must be reckoned to take place

within such limits. The attempt to surpass them would result not in an increase in rigour or

solidity but merely in cognitive paralysis (2004b, 191).

In other words, Wright concedes that on the question of evidential justification, the skeptic is correct. Let

us think of this as ‘evidential poverty’: evidentially speaking, hinge propositions have no more going for

them than their denials.9 Some anti-skeptical strategies do not concede evidential poverty. For example,

there is a long history attempting to show that 1MWH is evidentially superior to its competitors because

1MWH has super-empirical virtues that its competitors lack. The most common virtue cited is that of

simplicity: 1MWH is simpler than its rivals, and simplicity is evidence for truth, hence 1MWH is not

evidentially impoverished, that is, it is not underdetermined.10 11 Another possibility is to argue that 1MWH

9 I’ll say more about what I take Wright to concede to the skeptic towards the end of the following section.

10 To invoke Swinburne’s phrase (1997).

11 For an overview of this strategy, see Beebe (2009).6

is empirically supported after all. Some externalists, for example, say that justification amounts to beliefs

formed by reliable processes; so there is nothing wrong (in principle) with using perception to confirm that

perception is reliable (Van Cleve, 2003). Both strategies are less concessive than the entitlement strategy

since neither concedes that the skeptic has shown there are genuine limits to justification that undermine

the idea that 1MWH is evidentially justified.12 What makes the entitlement strategy of particular interest is

that it agrees with the skeptic about evidential poverty, but it questions the usual assumption that the fate of

the dogmatists’ position rests on the question of evidential poverty.

It will be useful to consider the entitlement strategy’s response to UA. The skeptic, recall, claims a

hypothesis must be evidentially justified in either an empirical or an a priori manner. It is precisely this

assumption that the entitlement strategy questions: justification comprises more than empirical and a priori

evidential justification. So, if the entitlement strategy is correct, UP must be false, because it ignores other

possible sources of justification. Hazlett has proposed the following principle that encapsulates an

entitlement strategy alternative to UP:

Security Principle (SP): “S’s justified hinge belief that P is defeated only if S has sufficient reason

to believe ~P.” (2006, 206).

One way to highlight the difference between UP and SP is in terms of defeaters. There is a common

distinction made between rebutting and undercutting defeaters (Pollock, 1986, 38-39). There is a rebutting

defeater for some belief p if there is a reason to believe not-p, or some proposition q that is logically

incompatible with p. There is an undercutting defeater for some belief p if there is no longer reason to

believe p, but no reason to believe not-p, or some logically incompatible proposition q. We shall refer to the

former as ‘dogmatic defeaters’ and the latter as ‘skeptical defeaters’ for reasons that will become apparent

as we proceed.  

We can see the effectiveness of SP in disarming the underdetermination argument. For suppose

1MWH is evidentially underdetermined: it has as much evidential weight in its favor as 2MtWH.

According to UP, it would follow that 1MWH is not justified. However, assuming 1MWH is a hinge

proposition, SP says that the underdetermination argument does not show that 1MWH is not justified, since

12 For criticisms of the former, see Walker (2016b). For criticism of the latter, see Walker (2016a). 7

the underdetermination argument offers no reason to believe ~P. That is, the underdetermination argument

offers only a skeptical defeater (2MtWH) to 1MWH, but what is required to show that 1MWH is not

justified according to SP, is a dogmatic defeater.

Wright’s formulation of the entitlement strategy also features a similar standard for defeat: “(i) X

has no sufficient reason to believe that P is untrue; and (ii) in all contexts, it is a dominant strategy for X to

act exactly as if he had a justified belief that P” 13 (2004b, 183). In terms of defeat, it is the first condition

that is important. It offers a higher standard for defeat in the sense that a skeptical defeater is not sufficient,

contrary to the underdetermination skeptic, a dogmatic defeater is required to defeat P. Thus, Wright too

offers reason to reject UP.

One of the most important insights of the entitlement strategy, touched on briefly above, is that it

takes seriously the idea that skepticism comes with a heavy epistemic cost—in addition to any practical

costs.14 In terms of epistemic cost, the choices are these: Either we do not trust perception, and so we must

renounce the possibility of having lots of knowledge about the external world, or, we trust perception and

accept the risk of false belief. The entitlement strategy says there are good epistemic reasons to prefer the

second choice. The point might be expressed in terms of epistemic risk and epistemic reward. Wright notes

that the entitlement strategy licenses a certain amount of risk:

…. we should view each and every cognitive project as irreducibly involving elements of

adventure—I have, as it were, to take a risk on the reliability of my senses, the

conduciveness of the circumstances, etc., much as I take a risk on the continuing reliability

of the steering, and the stability of the road surface every time I ride my bicycle (2004b,

190).15

13 Wright’s use of ‘justified’ here is the narrow sense indicated above, namely: evidential justification.

14 The claim that hinge propositions are epistemically justified, as opposed to merely pragmatically justified, has been challenged

by a number of authors. For the sake of the dialectic here, I will make the concessive assumption that this criticism is

unsuccessful. With specific reference to Hazlett’s paper, see Brueckner (2007). For a response to Brueckner, see Hazlett (2014).

For criticisms along the lines that Wright’s understanding of hinge propositions gives us, at best, pragmatic justification, see

Pritchard (2005 and 2015), Jenkins (2007) and Coliva (2015). For a response, see Wright (2012 and 2014).8

The risk, as noted, is false belief, and the reward is true belief. In most general terms, skeptics emphasize

the possibility of false belief. The entitlement strategy says that the cost of being risk aversive with the

skeptic is that we must renounce the possibility of justified belief or knowledge in the relevant area.

Clearly, assuming this line of reasoning is correct, this is a heavy epistemic price to pay.16

While this is not the place to review in detail competing conceptions of the notion of ‘hinge

proposition’, it is perhaps worth noting how the entitlement strategy differs from at least a couple of

competitors.17 One conception of ‘hinge propositions’ offers a non-propositional interpretation. For

example, Danièle Moyal-Sharrock understands hinge propositions as non-factual rules: “The

nonpropositional nature of basic certainties is one with their being ways of ‘acting’ and to their being

15 It is perhaps worth pointing out that Wright is at least wary of applying the entitlement strategy to ontological questions in his

(2004b), for reasons I can’t quite fathom. Hazlett has been the most forthright in applying the strategy to the ‘external world’.

16 There is an interpretative question for understanding Wright that I should mention here. Wright writes:

No doubt that will stand refinement, but the general motif is clear enough. If a cognitive project is

indispensable, or anyway sufficiently valuable to us—in particular, if its failure would at least be no worse than

the costs of not executing it, and its success would be better—and if the attempt to vindicate (some of) its

presuppositions would raise presuppositions of its own of no more secure an antecedent status, and so on ad

infinitum, then we are entitled to—may help ourselves to, take for granted—the original presuppositions

without specific evidence in their favour (2004b, 192).

The interpretative question is whether Wright is committed to what we might term a ‘Kantian,’ as opposed to ‘teleological,’

conception of what is at risk. The teleological understanding says the risk is some sacrifice which might be spelt-out in terms of

some ratio between true beliefs/false beliefs. The Kantian interpretation is that some hinge proposition is a constituent of some

cognitive project. That is, if we are to engage in some cognitive project, then we must accept some hinge proposition P. The

second sentence of the quote suggests that Wright may have both conceptions in mind. Here I often assume the teleological

interpretation, but clearly there are important differences between these two conceptions. However, the differences are not

important for present concerns because in either case, the entitlement strategy claims that something epistemically valuable (as

opposed to merely pragmatically valuable) is at risk. Thanks to Allan Hazlett for helping me work through this point.

17 For some helpful review of some of the different understandings of ‘hinge proposition’, see Pritchard (2015).9

‘animal’” (2016, 105). Another conception, due to Duncan Pritchard, has it that “rational support for our

hinge commitments are impossible” (2015, 71).18 On Pritchard’s conception, it is something like a category

mistake to look for justification—evidential or entitlement—for hinge propositions, for they are in some

sense arational. It should be clear from what has been said above that the entitlement strategy differs from

both the non-propositional and arational conceptions. On the entitlement strategy, hinge propositions are

truth-apt, and they are subject to rational support, that is, we may have a certain sort of justification for

them (albeit, not a traditional evidential justification). The importance of this going forward is that the

subsequent argument does not apply, at least not straightforwardly, to all attempts to invoke hinge

propositions as a means to address skepticism. In other words, the argument of this paper is somewhat

circumspect: I do not claim that a nonfactual or arational understanding of hinge propositions is subject to

the same sort of critique as the entitlement strategy.

This completes the initial sketch of the entitlement strategy. Some further features of the view will

be discussed in the following section as a possible rejoinder to radical underdetermination considerations.

Radical Underdetermination

As intimated above, the first criticism we will make is that evidential poverty leads to a stronger skeptical

conclusion than is commonly acknowledged. I will argue that it leads to a dogmatic defeater, and so

entitlement strategists, by their own understanding of defeasibility, should accept that 1MWH is defeated.

That is, by the entitlement strategy’s own account of hinge propositions, 1MWH is not a hinge proposition

because the radical underdetermination argument serves as a dogmatic defeater to 1MWH.

The basic issue turns on how we should respond to underdetermination considerations when there

are more than two competitor hypotheses. Consider that Berkeley’s immaterialism is sometimes discussed

in connection with the underdetermination argument for skepticism (Fumerton, 1992 and 2013). We should

consider:

3BWH: There are only minds and ideas; there is no material world.

18 It is worth noting that Pritchard argues that Wittgenstein’s notion of hinge propositions is better suited in application to

closure-based arguments, while epistemic disjunctivism is better suited to the sorts of underdetermination considerations

discussed in section 2. 10

3BWH is incompatible with 1MWH because 3BWH rejects (i), (iv) and (v) of 1MWH. We will assume too

that Berkeley’s explanation for immaterial substance does not invoke the idea of a computer simulation,

hence it is incompatible with 2MtWH.19

Once we see that there are at least three hypotheses to consider, we should ask: Do we have

evidential justification to favor 3BWH over 2MtWH, or vice versa? One thought here is that the skeptic

and the entitlement dogmatist will say the same thing about the pair-wise comparison of 3BWH and

2MtWH as was said about 1MWH and 2MtWH. Accordingly, let us imagine that 3BWH and 2MtWH are

evidentially equal. But once we expand our attention beyond the simple pairwise comparison, there is an

obvious difficulty: Our initial presentation of underdetermination skepticism in section 2 saw the skeptic

affirming that Pr(1MWH/e) = Pr(2MtWH/e), and now we are imagining the skeptic suggesting that

Pr(2MtWH/e) = Pr(3BWH/e), so it seems we are entitled to conclude Pr(1MWH/e) = Pr(3BWH/e) =

Pr(2MtWH/e). In which case, we have a positive reason to suppose that each hypothesis is probably false,

since the maximum epistemic probability of each can be no more than 0.33.20

A slightly less ambitious version of this argument, the disjunctive radical underdetermination

argument, may be summarized as follows:

DRU1: Radical Disjunctive Underdetermination Principle: If h2 and h3 are competitor

hypotheses to h1 and to each other, and e is all S’s evidence; and S’s evidence for believing

h1 is less than S’s evidence for believing (h2 or h3), then S is justified in believing h1 is

probably false.

DRU2: S’s evidence for believing 1MWH is less than S’s evidence for believing (2MtWH

or 3BWH).

DRUC: S is justified in believing that 1MWH is probably false (Walker, 2016b).

The argument is less ambitious because DRU1 does not depend on the oft criticized Principle of

Indifference: the idea that when we have no information favoring any alternative over another, then

19 3BWH and 2MtWH would have to be dressed up further to make sure they are logically incompatible. Adding these

complications adds nothing to our discussion, so I will leave it to the interested reader.

20 Here and below I will not fuss about small probabilities (0.01 and less).11

alternatives have equal epistemic probability.21 That is, DRU1 does not make the claim that the three

hypotheses are evidentially equal; rather, it makes the much more modest claim that no single hypothesis is

more likely than the combined epistemic probability of the other two.

The resulting view, that each of the metaphysical hypotheses about the external world is probably

false, is a form of error skepticism, or what we will refer to as ‘skeptical dogmatism’. Skeptical dogmatism

is the view that we ought to disbelieve each hypothesis, that is, we should believe each hypothesis is

probably false (Walker, 2015, 2016a, and 2016b). The reason that skeptical dogmatism is of relevance to

entitlement dogmatists is that the radical underdetermination argument extends the idea of evidential

poverty in pairwise comparisons to consideration of multiple hypotheses that are incompatible with a

(putative) hinge proposition. Indeed, although I cannot make the case here in detail, the argument above

shows there is reason to suppose the conditional claim is plausible: if you accept evidential poverty in the

pairwise comparison of 1MWH and 2MtWH, then you ought to accept that the radical underdetermination

argument shows that 1MHW is probably false (Walker, 2015).

It is worth pausing to consider one line of objection to the radical underdetermination argument.

The dogmatist might suggest that 2MtWH and 3BWH are simply ways of illustrating ~1MWH. So, the

entitlement strategy might claim:

A: Pr(1MWH/e) = Pr(2MtWH/e or 3BWH/e).

The trouble with this response is that unless the probability of 3BWH is 0.0, that is, unless we are certain

that 3BWH is false, it will follow that Pr(1MWH/e) > Pr(2MtWH/e), in which case, it is no longer clear

that the original underdetermination argument, which pitted 1MWH against 2MtWH, is a threat to

dogmatism. Hence, this line of response seems to call into question the need for the entitlement strategy in

the first instance. That is, if there is evidence that 1MHW is more epistemically probable given the same

batch of evidence than 2MtWH, then why do we need the entitlement strategy? It may be remarked that

indeed it is the case that Pr(1MWH/e) > Pr(2MtWH/e), but this is just to concede that the usual way of

illustrating the underdetermination argument is a bit sloppy. Since the upshot of the underdetermination

21 I happen to think that, when properly understood and properly qualified, the Principle of Indifference is far more plausible than

is generally assumed. For an interesting defense of the Principle of Indifference, see White (2010). 12

argument is supposed to be that Pr(1MWH/e) = Pr(~1MWH/e), it is just a bit careless to express the second

premise of the underdetermination argument above as:

UM: It is not the case that Pr(1MWH/e) > Pr(2MtWH/e).

Really, the premise should be stated as:

UM*: It is not the case that Pr(1MWH/e) > Pr(~1MWH/e).

This doesn’t really advance the issue though, because if 2MtWH and 3BWH both have some positive

probability, the following inequalities must be admitted:

IN1: Pr(1MWH/e) > Pr(2MtWH/e).

IN2: Pr(1MWH/e) > Pr(3BWH/e).

So, the difficulty for the underdetermination skeptic is to say what evidence favors 1MWH over 2MtWH,

and 1MWH over 3BWH. The argument in section 2 suggests that the evidence for favoring 1MWH must

be either empirical or a priori. But this puts those who endorse the view that there is not a dogmatic

defeater for 1MWH, e.g., proponents of the entitlement strategy, in the embarrassing position of having to

say that there is either empirical or a priori evidence that favors 1MWH over 2MtWH, and there is either

empirical or a priori evidence that favors 1MWH over 3BWH. If there is such evidence, then surely we are

owed some account of this. What evidence is there that favors 1MWH over each of the disjuncts, 2MtWH

and 3BWH? It would seem that the entitlement strategy will need to help itself to one or more of the

aforementioned anti-skeptical strategies, e.g., appealing to the super-empirical virtues of 1MWH, etc., to

say why 1MWH is evidentially superior to each of 2MtWH and 3BWH. Of course, the entitlement

strategist will need to be careful that such reasons for favoring each of the disjuncts do not lead to favoring

1MWH over the entire disjunction of skeptical possibilities, for then the need for entitlement justification is

far less urgent. It is far from clear that such a delicate (miraculous?) balancing act can be carried out.

Certainly it is not one that entitlement strategists have even attempted at this point.

13

To illustrate a further difficulty, let us suppose that there are only two competitor hypotheses to

1MWH, so that ~1MWH = 2MtWH or 3BWH.22 In which case, the claim that Pr(1MWH/e) = Pr(2MtWH/e

or 3BWH/e) seems entirely arbitrary. Suppose Berkeley adopts the entitlement strategy to defend his

idealism. He claims:

B: Pr(3BWH/e) = Pr(1MWH/e or 2MtWH/e).

His concession to evidential poverty is that while his writings show the superiority of 3BWH over each of

the disjuncts 1MWH and 2MtWH, still he concedes that their combined probability exactly equals 3BWH.

But, if the epistemic probability of 2MtWH is not 0.0, then propositions A and B are incompatible. It would

seem entirely arbitrary, given the acceptance of evidential poverty, to choose A in preference to B.

The challenge to the entitlement strategy is readily apparent. If the radical underdetermination

argument is correct, and 1MWH, 2MtWH, and 3BWH are competitor hypotheses, then each hypothesis is

defeated by a dogmatic defeater. In each case, there is reason to favor the negation of each hypothesis, that

is, Pr(~1MWH) > Pr(1MWH), Pr(~2MtWH) > Pr(2MtWH), and Pr(~3BWH) > Pr(3BWH). In which case,

Wright and Hazlett must concede that each hinge proposition, 1MWH, 2MtWH, and 3BWH is defeated by

a dogmatic defeater.

In other words, the dilemma for the entitlement strategy is this: Either the entitlement strategy takes

evidential poverty seriously or it doesn’t. If it takes evidential poverty seriously, then the entitlement

strategy must concede that each of the individual explanatory hypotheses for perceptual experience,

1MWH, 2MtWH, and 3BWH, is defeated. If evidential poverty is renounced in order to save 1MWH from

defeat, e.g., by claiming that 1MWH has greater evidential weight than each of 2MtWH and 3BWH, then

the need for the entitlement strategy is less clear, since 1MWH seems to have something special going for it

—evidentially speaking. If it is maintained that 1MWH has just enough going for it, evidentially speaking,

such that it is favored over each of the disjuncts, but not the disjunction, then we are owed some account of

how this very delicate balance is achieved, and how it is not arbitrary. In either case the sufficiency of the

entitlement strategy, at least as it has been articulated thus far in combatting underdetermination

skepticism, is called into question.

22 This assumption clearly favors the dogmatist about 1MWH (Walker, 2015). 14

Consider the following objection to the above dilemma.23 Suppose evidential poverty is accepted,

hence, 1MWH has nothing more going for it, evidentially speaking, than its alternatives. However, what an

entitlement provides us with is justification for putting to one side probabilistic considerations and

accepting 1MWH as true anyway. Given that probabilities naturally go together with evidence, and that

entitlement is a non-evidential species of justification, it follows that entitlement isn't best thought of in

terms of justifying a particular evidential probability. Rather, what entitlements do is justify a certain non-

probabilistic acceptance of 1MWH. This is compatible with there being entitlements for 2MWH and

3MWH also.

I believe there is something right—indeed, helpful—about this ‘non-probabilistic’ line of objection,

and something wrong depending on whether we are reasoning in the ‘everyday mode’ or the ‘reflective

mode.’ By ‘everyday mode,’ I mean the idea that we make use of our entitlement to hinge propositions

when making everyday claims. By ‘reflective mode,’ I mean the idea that we enquire about the status of

candidate hinge propositions. Let us take these in turn.

The non-probabilistic understanding of hinge propositions in the everyday mode may be understood

as follows: the evidential uncertainty of hinge propositions is ‘bracketed’ in such a way that it does not

affect my thinking and responses to questions about the probability of everyday matters. To ‘bracket’ such

concerns means simply to acknowledge that the justification I have for a hinge proposition is not entirely

determined by its evidential standing. In Wright’s bicycle analogy, in a moment of quiet philosophical

reflection, I may acknowledge that without such bracketing there are a number of risks associated with

riding a bike. But when riding a bicycle, I typically bracket such concerns and fully trust in the reliability of

the steering, that the road will not turn to liquid, etc.

We can think further about probabilistic reasoning by using another example from Wright. Consider

this line of reasoning:

(I) My current experience is, in all respects, as if it is raining.

(II) It is raining.

(III) There is a material world (Wright, 2004b).

23 My thanks to an anonymous referee for raising this objection. 15

According to Wright, when we reason from type (I) propositions to type (II) propositions we presuppose

the truth of type-III propositions.24 What seems clear is that on the entitlement strategy, the evidential

uncertainty associated with (III) does not affect our evidential probability estimate of the everyday

proposition asserted in (II). It would be wrong, for example, to answer your spouse’s question about the

likelihood of rain tomorrow as 0.25 based on the following line of reasoning: The tv report says that there

is a 0.5 chance of rain tomorrow, and, because of evidential poverty, you believe that there is a 0.5 chance

that there is a material world, and a 0.5 probability that it is not a material world. (You understand your

spouse to be asking about material rain, rather than any non-material thing that looks like rain.) Wright’s

entitlement view, as I understand it, is committed to saying that the correct answer is 0.5. To use the lower

number is to, in effect, double-count, evidential poverty. On such an understanding, in the reflective mode

we may acknowledge the risk of the entire cognitive project, in this case perception, and acknowledge

evidential poverty again in the everyday mode for everyday propositions. Instead, the entitlement strategy

is better seen as suggesting that we are permitted to bracket questions of evidential poverty for everyday

propositions and the associated risks when we have entitlement justification for the associated hinge

propositions. So, if we have entitlement justification for (III), we are required (or at least permitted) to use

the 0.5 probability estimate for rain.

To question whether a candidate hinge proposition is in fact a hinge proposition is to engage in the

reflective mode. In this mode, we ask whether a candidate hinge proposition meets the conditions for being

a hinge proposition. As we noticed on Wrights’ version of the hinge strategy, two conditions must be met.

The candidate hinge proposition must be indispensable for some cognitive project and there must be no

dogmatic defeater for the candidate hinge proposition. Suppose, for example, that I take the claim, “It will

not rain on Saturday” as a hinge proposition. When asked by a friend why I treat this proposition non-

probabilistically, for example, ignoring my friend’s observation that the forecast says there is a 50% chance

of rain on Saturday, I claim that good weather is an indispensable condition for my wedding plans. Since it

is a hinge proposition, I understand it non-probabilistically, hence, I am permitted to ignore such

probabilistic considerations in my reasoning about the weather on my wedding day. But clearly this

putative hinge proposition, “It will not rain on Saturday,” is not in fact a hinge proposition. The proposition

is not indispensable for a cognitive project no matter how important its truth might be for my wedding

24 This is similar to the point Wright has pressed against Moorean-type responses to skepticism. See, for example, (2007). 16

plans. So, it would be wrong to appeal to the non-probabilistic understanding of a hinge proposition in this

case to explain my non-probabilistic understanding of “It will not rain on Saturday,” since the proposition

fails to meet one of the requirements for a hinge proposition. In other words, if there is some reason to

suppose that I am permitted to use the non-probabilistic understanding of “It will not rain on Saturday,” it

cannot be because this proposition is a hinge proposition.

A similar point applies when considering the second, no-dogmatic defeater condition: in the

reflective mode, one might find that a candidate hinge proposition does not meet the no-dogmatic defeater

condition. Think of the example of the character Neo from the Matrix movies. It is plausible to assume that

Neo originally met the conditions for accepting (III) as a hinge proposition: it is indispensable for the

cognitive project of perception (let us grant), and the movie initially depicts Neo living an ‘epistemically

normal’ life where he has no-dogmatic defeater for (III). As the movie progresses, Neo encounters

mounting evidence against his previous acceptance of (III). That is, Neo learns about how the virtual reality

of the Matrix operates, and how it was designed to deceive him and all those immersed in the Matrix, so

Neo acquires a dogmatic defeater for his previous acceptance of (III). The non-probabilistic understanding

of hinge propositions will not help in this instance, for let us suppose the question before Neo in the

reflective mode, where he asses this evidence against (III), is whether (III) meets Wright’s conditions for a

hinge proposition. But after learning about the machinations of the Matrix, Neo cannot rationally accept

(III) as a hinge proposition, since (III) fails to meet the no-dogmatic defeater condition. Wright himself

cites ‘The Matrix’ as an example where beliefs are “detached from reality in a certain way” (2004b, 168).

The movie may be interpreted as making a compelling case for the idea that Neo, in the reflective mode,

has very good evidence—sufficient for a dogmatic defeater—that his former beliefs suffered from exactly

this sort of detachment from reality.

A similar point applies to thinking about (III) in the reflective mode in light of the radical

underdetermination argument: (III) cannot have the status of a hinge proposition for anyone who accepts

the radical underdetermination argument, precisely because the no-dogmatic defeater condition is not met

for (III). Again, the non-probabilistic understanding of hinge propositions is of no avail here in defending

(III) because, trivially, for the non-probabilistic understanding of hinge propositions to apply, the candidate

proposition must in fact be a hinge proposition. Since (III) fails to meet one of the necessary conditions for

candidate hinge propositions on Wright’s account, (III) cannot be a hinge proposition for those who have

17

mental state dogmatic defeaters for (III). In other words, the non-probabilistic understanding of hinge

propositions cannot be used to address the logically prior question of whether a candidate proposition is, in

fact, a hinge proposition.

So, it may be granted (at least for the sake of the argument) that the non-probabilistic understanding

of hinge propositions provides a good explanation for reasoning probabilistically in the everyday mode. In

the reflective mode, however, the non-probabilistic interpretation cannot be invoked to save candidate

hinge propositions from the radical underdetermination argument. The reason, again, is that the radical

underdetermination argument’s conclusion implies that 1MWH, 2MtWH, and 3BWH fail to meet Wright’s

conditions for hinge proposition status.25

Entitlement and Competitor Hinge Propositions

In this section, we will lay the groundwork for the second criticism by focusing on the claim that hinge

propositions play some fundamental role in our epistemic lives. Their fundamental nature has been

described as “indispensable,” “non-optional,” “methodological necessities,” and “essential” for any

epistemic evaluation (Grayling, 2008; Pritchard, 2015, 199; Williams, 1991, 123; Pritchard, 2012b). Wright

explains this role in terms of a presupposition: “P is a presupposition of a particular cognitive project if to

doubt P (in advance) would rationally commit one to doubting the significance or competence of the

project” (2004b, 191). Consider a Moorean-type illustration:

1. I know I have hands.

2. If I know I have hands, I know 1MWH.

3. I know 1MWH.

25 The distinction between the everyday and reflective mode is similar, and may be the same as Wright’s distinction between

‘possession’ and ‘claims’ to warrant (2014, 219-221). One potential difference is that Wright emphasizes defending hinge

propositions in his discussion of claims to warrant, e.g., Wright writes: “As a first approximation to an answer [about the

meaning of ‘rational claims to warrant’], I have in mind whatever one might relevantly enter into an attempt to substantiate the

assertion, perhaps in the face of a challenge, that one is indeed warranted in accepting a certain proposition” (2014, 220). In the

reflective mode, candidate hinge propositions may be accepted or rejected. If Wright allows this when speaking about claims to

warrant, then the distinctions may be the same. Thanks to an anonymous referee for pointing out this parallel. 18

Doubting 3 seems to raise wholesale doubts about the competence of perception, for it seems we can run a

similar argument, mutatis mutandis (at least), for many claims to know about medium sized objects in our

local environment. If we doubt 3, then it seems we should doubt many claims about everyday objects (via

modus tollens). It seems then that 1MWH has a very good claim to be a presupposition, in Wright’s sense,

of the cognitive project of perception.

Notice however that at best, this line of argument shows that 1MWH is a hinge proposition. It does

not show that other hinge propositions might also be appealed to. Consider for example the possibility of

appealing to 3BWH as a hinge proposition. Berkeley, as is well-known, spent considerable energy thinking

about the “competence and significance” of perception, given his idealism. Berkeley agrees, indeed stresses

at great length, that we see, interact with, and know about macroscopic objects, tables, trees, teacups, etc.,

but adds that we perceive only ideas, so macroscopic objects are ideas (Winkler, 1989, 138). Berkeley

writes:

I do not argue against the existence of any one thing that we can apprehend by sense or

reflexion. That the things I see with my eyes and touch with my hands do exist, really exist,

I make not the least question. The only thing whose existence we deny is that which

philosophers call Matter or corporeal substance. And in doing of this there is no damage

done to the rest of mankind, who, I dare say, will never miss it (1982, §35).

To see this point in relation to hinge propositions we might imagine an alternate history. In actuality,

Berkeley sought and failed to find sufficient economic and political support to establish a school in

Bermuda. Suppose, however, that he had succeeded in establishing his school and an idealistic metaphysics

is the norm for those in the Bermuda academic community that persists long after Berkeley has gone. We

can also imagine a philosopher named ‘Less’ teaching at Berkeley’s school a couple of hundred years after

Berkeley’s death, promulgating the following sort of argument:

1. I know I have hands.

2*. If I know I have hands, I know 3BWH.

3*. I know 3BWH.

19

Imagine too, Professor Less claims that while 3* is subject to worries that arise from evidential poverty, 3*

is justified because it is a hinge proposition that enjoys entitlement justification. These reflections show that

even if we concede that there must be some hinge proposition associated with the cognitive project of

perception, it does not follow that it must be 1MWH. 3BWH would serve just as well for members of an

idealistic community as 1MWH does for a materialistic community.

Similar things can be said about the possibility that 2MtWH might serve as a hinge proposition.

Suppose one of your high school friends, after watching the movie The Matrix for the two hundredth time,

comes to believe 2MtWH and rejects 1MWH. He insists that you call him ‘Neo’ (the aforementioned

protagonist in the movie) and out of respect for his stupid wishes, you do. Neo believes his perception is

reliable. When he sees a virtual mailbox, he avoids it. He knows that running into virtual mailboxes in the

Matrix hurts. Thus, 1MWH is not the only hypothesis compatible with trusting perception. And indeed, in

those possible worlds where Neo is correct that he is living in 2MtWH, his perception is working reliably.

(By ‘working reliably’ I have in mind the Goldmanian sense of a method for generating true beliefs.) While

Neo’s friends may be deceived if 2MtWH is true (since they believe 1MHW), Neo himself will have all

sorts of true beliefs about virtual objects in their shared virtual environment.

What should we say about whether the Berkeleyian community is justified in believing 3BWH, or

whether Neo is justified in believing 2MtWH? The entitlement dogmatist about 1MWH may say that

1MWH is justified to a greater degree than 2MtWH or 3BWH for us because of its role as a hinge

proposition in our thinking. But of course Neo will make the same argument for his preferred hinge

proposition: the belief in 2MtWH is as much a hinge proposition for him as 1MWH is for dogmatists about

1MWH. If we accept that 2MtWH is a hinge proposition, then we have reason to think that 2MtWH is

justified for Neo. The same point will apply, mutatis mutandis, for the Berkeleyians and their hinge belief

that 3BWH is true.

Notice that the additional justification each ‘home’ hinge proposition enjoys for each group is

entitlement justification, not evidential justification. After all, by assumption, evidential poverty applies, so

each hypothesis is equally justified when focusing on specifically evidential considerations. The different

entitlement justification for each group stems from the fact that each group employs different hinge

propositions in their cognitive lives.

20

I don’t mean to suggest that this is any sort of reductio of the entitlement strategy. To make such an

argument depends upon, among other things, the idea that this sort of epistemic relativism is an

unacceptable consequence. Here ‘epistemic relativism’ means that the same total body of evidence may

equally support two or more incompatible hypotheses, such that there is “faultless disagreement” (Luper,

2004; Pritchard, 2009).26 At least some proponents of the entitlement strategy—e.g., (perhaps) Wittgenstein

and Hazlett—seem willing to endorse the idea of epistemic relativism in this sense.27

The main point for us here is about the necessity of believing 1MWH in order to trust perception.

Recall Hazlett says, “If one failed to believe in the external world [i.e., 1MWH], one would be forced, if

rational, to distrust perception at the very least, and this would result in the sort of confusion described”

(2006, 206). As the Neo example illustrates, it is possible to adopt an incompatible proposition to 1MWH

yet not distrust perception. Neo believes 2MtWH and trusts his perception: he believes he is seeing virtual

artifacts and he uses perception to navigate in the virtual world. So, the choice is not distrusting perception,

or adopting 1MWH as a hinge proposition. At best, what follows from the entitlement strategy premises are

that one must adopt a hinge proposition that says something about the trustworthiness of perception, and as

we have seen with Less and Neo, nothing in the entitlement hinge proposition strategy mandates that it

must be 1MWH.

I suspect that most dogmatists about 1MWH believe that (1) 1MWH is justified, and (2)

competitors to 1MWH are not justified. Skeptics, of course, challenge (1) and allow (2). As we have just

seen, the entitlement strategy allows that (1) is true and (2) is false. This is perhaps not too surprising given

that, as Wright says, the entitlement strategy is “concessive” to skepticism. So perhaps we should not be

surprised that the entitlement strategy does not single out a particular hinge proposition, since evidence

does not settle the issue (according to the entitlement strategy), and entitlement justification does not

differentiate between competitor hinge propositions. For dogmatists who hope to be in a position to assert

both (1) and (2), the hinge strategy can only disappoint.

26 Also seemingly relevant here is the uniqueness/permissiveness debate in the disagreement literature.

27 For Hazlett’s take on relativism, see his (2014). It is pretty common to interpret Wittgenstein as an epistemic relativist. For

some review and dissent, see Coliva, (2010b).21

Phenomenalism

The argument so far does not address an important point—perhaps the fundamental point of the entitlement

strategy—that there is a huge epistemic cost to pay if we do not accept hinge propositions, namely, we

must distrust perception as a source of justified belief and knowledge. In effect, we may understand the

entitlement strategy as proposing the ‘entitlement conditional’:

EC: If we trust perception, then we have entitlement justification for some hinge proposition

about the external world.

Assuming EC, and the previous argument that there is not entitlement justification for each of the particular

hinge propositions about the external world (since they each face a dogmatic defeater), then by modus

tollens, it would seem we ought not to trust perception. This would be a rather difficult conclusion to accept

—to put it mildly. The rest of the paper will focus on showing how EC might be denied by two different

epistemological theories: phenomenalism and external world disjunctionism.

Let me say right off that I’m not suggesting we revive phenomenalism; the problems with

phenomenalism are well-known.28 Rather, the main reason for our quick review of phenomenalism is to see

that even where evidential poverty is conceded, there is at least one alternative to the dilemma suggested by

EC: either we distrust our senses entirely or we endorse the entitlement strategy. The idea then, will be to

look for an alternative to phenomenalism that has phenomenalism’s virtues but not its vices.

Perhaps phenomenalism’s greatest sales pitch is that it offers a way to purge ourselves of

skepticism and metaphysics in one fell swoop. As Barry Stroud notes, it offers a strategy to close the

epistemic gap between perception and the world: “One strategy was to try to bring the world we believe in

closer to what we can perceive; every meaningful and potentially knowable proposition about the world

was to be expressed exclusively in terms of possible sense experience” (2004, 182). So, according to

phenomenalism, to believe there is a desk in front of me is just to believe that certain sense data are being

28 A classic statement can be found in Ayer (1954). The locus classicus against a reductive equivalence can be found in Chisholm

(1948). A good summary of various problems for phenomenalism can be found in BonJour, (2007). For a recent defense of

phenomenalism, see Pelczar (2018). 22

experienced (e.g., a brown patch in my visual field) in one version, and in another, by reducing talk about

the material world to “permanent possibilities of sensation” (Mill, 1889).

Thus, one of the advantages phenomenalism offers is a means to dissolve the metaphysical

differences between 1MWH, 2MtWH, and 3BWH. The hope is that whatever sense data story is told about

a brown material desk, there is an equivalent sense data story in terms of a virtual brown desk or an

immaterial brown desk. That is, the hope is that with phenomenalism, the definition (or the ‘definition in

use’, as Ayer used to like to say) for a brown material desk, a brown immaterial desk, or a brown virtual

desk is the same in the language of phenomenalism (e.g., ‘a brown patch in my visual field’). And of

course, perception is important for phenomenalists as a means (or perhaps the means) to become

acquainted with sense data. So, if phenomenalism is viable, it at least holds the promise of eliminating the

metaphysical dispute—since metaphysical claims can be reduced to the common language of sense data.29

With respect to underdetermination considerations, phenomenalism denies that 1MWH, 2MtWH,

and 3BWH are incompatible, for, to the extent that they are meaningful, all can be reduced to the common

language of possible sense data. Thus, phenomenalists are in a position to reject U2 of the

underdetermination argument and RU2 of the radical underdetermination argument precisely because

1MWH, 2MtWH, and 3BWH are not incompatible, but merely notational variants. In other words, the

skeptic’s argument and the skeptical dogmatist’s argument assume that the metaphysical hypotheses are

incompatible. If successful, the reductive program of phenomenalism would show this assumption is false

and hence, neutralize any skepticism based on this assumption.

On the other hand, phenomenalism would permit us to trust perception. According to

phenomenalism, I am in a position to trust perception to justify my belief that there is a brown desk in front

of me because for it to be true that there is a brown desk in front of me is simply to have a certain set of

sensations. So, for there to be a brown desk in front of me is just to have a set of sensations, “to be

appeared to brown deskly.” In other words, I am entitled to reason as follows: Since there appears to be a

brown desk in front of me, there is a brown desk in front of me.

External World Disjunctivism

As noted, it is commonly thought that phenomenalism’s reductive program of translating ‘world talk’ into

talk of ‘possible experience’ turned out to be implausible, if not impossible. Let us assume this thought is

29 For criticisms of the plausibility of this sort of response to skepticism, see Coliva (2015).23

true. The question for us is whether there is a way to neutralize the metaphysical differences between

1MWH, 2MtWH, and 3BWH without having to commit to the reductive program of phenomenalism.

I will argue that external world disjunctionism (EWD) satisfies these desiderata. The notion of

‘external world’ in EWD is the one noted above: the rather generic sense that simply means any sense of

the world other than me. 1MWH, 2MtWH, and 3BWH are to be understood as different hypotheses about

the nature of the external world in this sense. (So, ‘external world’ does not mean the same thing as

1MWH.) The idea behind EWD, in a nutshell, is to refuse to play metaphysical favorites by using

disjunction. The key methodological principle is:

External World Disjunctionism Principle: If M1 and M2 are evidentially equal competitor

metaphysical hypotheses about the external world, and M1 is accepted as justified as part of our

metaphysics, then M2 should be accepted as part of our metaphysics.30

EWD says that if we accept 1MWH and concede that 2MtWH is evidentially equal to 1MWH, then we

should accept 2MtWH as part of our metaphysics. That is, we should accept:

1EWD: 1MWH or 2MtWH is true.

Similarly, if it is conceded that 3BWH is evidentially equal to 2MTWH, then 3BWH should also be

included as part of our metaphysics.31 In which case, we should accept:

30 I use the generic ‘acceptance’ here to cover whatever propositional attitude is appropriate with respect to metaphysical

hypotheses. Acceptance covers such possibilities as ‘acceptance’ in Wright’s (2004b) sense, as well as belief and knowledge. For

our purposes, it does not matter.

31 To avoid unnecessary complications in the exposition, I will assume that the metaphysical hypotheses are evidentially equal.

As noted above in connection with the radical disjunctive underdetermination argument, this assumption can be relaxed—we do

not need to endorse the principle of indifference. Similarly, EWD could be formulated in a more modest fashion in terms of the

denial that any particular hypothesis is evidentially weightier than the combined epistemic probability of two other incompatible

hypotheses. 24

2EWD: 1MWH, or 2MtWH, or 3BWH is true.

In terms of its virtues, I will suggest that EWD does not pose an obstacle to trusting perception to

obtain knowledge about our environment sufficient for everyday purposes, even while conceding that

perception cannot discriminate amongst the various metaphysical hypotheses to explain experience. To

illustrate, imagine for the moment that you believe EWD and you are trying to persuade three companions,

a materialist, an idealist, and a virtualist (someone like Neo, who believes we are in a virtual reality), of

EWD virtues as you walk down a street. Your companions, incredulous of such a position and dead-set on

dogmatism with respect to their preferred hinge positions, are so engrossed in the conversation that they are

oblivious to an object in their path. You call out, “Watch out for the material mailbox, or the immaterial

mailbox, or the virtual mailbox in front of you.” True, the ‘mailbox disjunction’ is a bit wordy, but it shows

that even as a proponent of EWD you can trust perception enough to help your companions avoid one of

three different potential pitfalls. After all, although you accept that while your sensory evidence is not

sufficient to distinguish material, immaterial, and virtual mailboxes, past experience suggests that running

into a mailbox, however ‘mailbox’ is disambiguated, can be very painful.32

A few points are worth noticing here. First, your companions are not in a position to plausibly

question the truth of what you have said, since each will be committed to the truth of one of the disjuncts.

Hence, rationally, they should be committed to the truth of the disjunction. So this means that there is an

interesting asymmetry here: each of your companions may agree with you about the mailbox disjunction

even while they disagree with each other. If your companions have any complaint with respect to EWD, it

is that your statement is too generic; you should commit to one of the disjuncts (presumably, their preferred

disjunct).

Second, the vital role of perception for EWD is obvious when we reflect that it does not follow

trivially that if we are in a material world, then there is a material mailbox in the path of your companions;

and it does not follow trivially that if we are in an immaterial world, then there is an immaterial mailbox in

the path of your companions; and it does not follow trivially that if we are in a virtual world, then there is a

32 One could, of course, question inductive reasoning, but here we confine our attention to underdetermination skepticism about

the senses. 25

virtual mailbox in the path of your companions. Trusting perception is vital to obtaining justified belief

about the presence of the object referred to by the mailbox disjunction.

To put the point starkly: imagine the ever-cruel god of epistemology offers a tragic choice. She will

tell you which of the various metaphysical hypotheses (1MWH, or 2MtWh, or 3BWH) offered to explain

the character of our experience is true, but the price is that all your perceptual capacities will be

incapacitated forever. Or, you can use your perceptual capacities to navigate your environment, but the true

metaphysical hypothesis (1MWH, or 2MtWH, or 3BWH) will never be revealed to you. I suspect that most

of us would choose the latter. But for our purposes it does not matter which option is preferred. What

matters for our purposes is this point: knowing which metaphysical hypothesis is true provides only a part

of what we might like to know. Conversely, there is still much we can know about our world, like the

mailbox disjunction, even if we do not have the additional knowledge of which particular disjunct is true.

Third, EWD provides immunity from the underdetermination skepticism previously considered. For

example, consider attempting to mount an underdetermination argument against belief in 2EWD. The

skeptic or the skeptical dogmatist might suggest that there are other competitor hypotheses to those

mentioned in 2EWD. For example, the idea that we are brains in a vat living in a virtual world orchestrated

by a mad scientist (4BIVWH), or there is an evil demon causing us to have experiences (5EDWH), or that

we are in some deep dream state that is being manipulated by others as in the movie Inception (6IWH).33

The skeptic then suggests that the following hypothesis has as much going for it, evidentially speaking, as

2EWD:

3EWD: Either 4BIVWH, or 5EDWH, or 6IWH is true.

The skeptic claims that 2EWD and 3EWD are equally potent, so the underdetermination argument is not

thwarted. However, EWD directs us to include the three additional hypotheses, so we should accept:

4EWD: Either 1MWH, or 2MtWH, or 3BWH, or 4BIVWH, or 5EDWH, or 6IWH is true.

33 An even larger variety of competitor hypotheses can be found in Walker (2015).26

The point then, is that such underdetermination considerations can always be thwarted by adding disjuncts

to the disjunction.34

Fourth, even EWD’s recommendation for a more modest role for perception in justifying belief is

consistent with perception ruling out some metaphysical hypotheses that might be used to explain the

nature of our world. For example, the author’s wish world hypothesis:

7AWWH: Everything I wish for comes true.

My senses confirm that 7AWWH has less going for it, evidentially speaking, than say 1MWH. It appears to

me that many of my wishes do not come true. I wish for an end to war and violence. I wish for an end to

starvation, disease, and death. I wish for fewer committee assignments. It might be remarked that perhaps

all these things have come true, but I have been deceived about the satisfaction of these wishes, so the fact

that my senses provide evidence that 7AWWH is false does not show that 7AWWH is false. However, one

of my wishes is that I am not in error about such matters, so I still have confirmation that 7AWWH is false

since it appears to me that none of these things is true. It seems that reflecting on the nature of our

perception might also lead to rejecting a neo-Parmenides hypothesis that Being is unchanging. My

perceptual experience itself seems to be changing. Since my perceptual experience is part of Being in

general, a hypothesis like 1MWH has more going for it, evidentially speaking, than the neo-Parmenides

hypothesis.35

34 While this is not to make the argument in detail, it should be clear that EWD promises some help with closure-based

arguments for skepticism.

35 I refer to this as a ‘neo-Parmenides hypothesis’, as it is inspired by Parmenides, but it may be different depending on how one

understands Parmenides’ notion of ‘Being’. On the one hand, Parmenides appears to contrast Being with how Being is perceived,

and on the other, the notion of Being sounds very totalizing, seeming to include all that is. This is the line of thought that inspires

the notion that even perceivers are unchanging qua parts of Being. I am neutral on the attribution to Parmenides here, since I’m

not sure what to make of this interpretative problem. I owe a debt a gratitude to an anonymous referee for prompting this

distinction. 27

Disjunctionism or Disjunctivism

It may help to distinguish disjunctionism from disjunctivism, given the recent surge of interest in the latter,

and apparent similarities—at least in name—between the views. It is common in expounding disjunctivism

to classify perceptual experience into ‘good cases’ and ‘bad cases,’ the former covering veridical perceptual

experience, and the latter, illusions and hallucinations (Soteriou, 2010). Very roughly, disjunctivism says

that veridical and non-veridical cases of perception may be treated differently. In what is known as its

‘metaphysical form,’ disjunctivism says that the ‘components’ of experience differ in good and bad cases.36

In its epistemological form, disjunctivism says that there may be an evidentiary (reasons or justification)

difference between perception in good and bad cases.37 I will concentrate on disjunctivism in its

epistemological form, as it is the one most commonly associated with having anti-skeptical consequences. I

shall suggest that they are logically independent responses to the radical underdetermination skeptic’s

reasoning in the sense that the truth or falsity of one does not imply the truth or falsity of the other.

However, given the variety of disjunctivists views that have been developed, and their complexity, it will

be necessary to address these issues in very broad strokes. A more detailed treatment of the issue would

require a much longer discussion than is appropriate here.38

To simplify the discussion, let us suppose that we know that the mailbox disjunction is true and ask

what the radical underdetermination skeptic, the disjunctivists, and disjunctionist make of this fact. The

radical underdetermination skeptic, we may suppose, will point out that (i) it is subjectively indiscernible

whether the materialist, immaterialist, or virtualist in fact sees a material, virtual, or immaterial mailbox;

(ii) hence, experience supplies the materialist, immaterialist, and virtualist with the same reasons for their

36 See, for example, Martin (2002).

37 Perhaps the clearest exposition of this view can be found in Pritchard (2012). In this work, Pritchard notes the seminal role

John McDowell’s work has played in formulating epistemological disjunctivism.

38 To indicate just some of the difficulties here, to the best of my knowledge, no epistemological disjunctivist has addressed

radical underdetermination skepticism. Consider that perhaps most sustained recent discussion of epistemological disjunctivism

with respect to external world skepticism is due to Pritchard (2012 and 2015). Pritchard develops an account of disjunctivism

which incorporates a notion of defeaters, including misleading defeaters. One question going forward is whether radical

underdetermination skepticism can be used to show against disjunctivism that we have defeaters for our perceptually-based

beliefs. 28

perceptually-based beliefs; (iii) hence, we should distrust perception. Let us take it that all parties agree that

(i) is true.39

The epistemological disjunctivist, let us suppose, claims that the inference from (i) to (ii) is

problematic, for disjunctivists allow that there is an asymmetry in the evidence that experience supplies in

the mailbox case. For either the materialist, immaterialist, or the virtualist, experience provides a reason

that it is the case that her belief is true, for the other two it does not provide such a reason.40 In McDowell’s

terminology, two of the three are deceived: the object of their perception is “mere appearance,” but for the

third, it is the case that “the fact itself being disclosed to the experiencer.”41 With reference to the radical

underdetermination argument, we might suppose that the epistemological disjunctivist rejects the reasoning

which leads to DRU2. The disjunctivist’s thought here is that DRU2 is supported by the anti-disjunctivist

assumption that because 1MWH, 2MtWH, and 3BWH are subjectively indistinguishable, it follows that

perception provides no more reason for perceptually based beliefs in both the good and bad cases. But as

we have just seen, the disjunctivists rejects this inference. To show the independence of disjunctionism and

disjunctivism on this point, suppose in addition that disjunctionism is false. This will not affect the

disjunctivist’s claim that the inference from (i) to (ii) ought to be rejected. So, disjunctivism may be true

while disjunctionism is false.

The disjunctionist, on the other hand, may grant that the radical underdetermination skeptic is

correct in pressing (ii), but will deny the inference to (iii). In effect, the disjunctionist’s counterclaim is to

deny that we must distrust perception completely, even if we should distrust perception to distinguish

39 For more on what indistinguishability amounts to in such cases, and why epistemological disjunctivists may grant this, see

Pritchard (2012) and Fish (2008).

40 As is often emphasized, if disjunctivism is importantly different from externalism in ascribing a different epistemological

standing to subjects in good cases, then disjunctivism must be understood along internalist lines (Pritchard, 2012a). Here we

follow McDowell and Pritchard in thinking that experience in the good case actually entails the truth of the believed proposition.

41 As suggested by this famous passage from McDowell: “As before, the object of experience in the deceptive cases is a mere

appearance. But we are not to accept that in the non-deceptive cases too the object of experience is a mere appearance, and hence

something that falls short of the fact itself. On the contrary, the appearance that is presented to one in those cases is a matter of

the fact itself being disclosed to the experiencer. So appearances are no longer conceived as in general intervening between the

experiencing subject and the world” (1998, 386-387). 29

between each of the mailbox disjuncts. Nothing in the radical underdetermination argument shows that

perception does not provide us with reason to believe the mailbox disjunction, even if we have reason to

suppose that each disjunct is probably false. To show the logical independence of disjunctionism and

disjunctivism on this point, suppose in addition that disjunctivism is false. This will not affect the

disjunctionist’s claim that the inference from (ii) to (iii) ought to be rejected. So, disjunctionism may be

true while disjunctivism is false.

If we allow that radical underdetermination skepticism is a possible position, then we have a case

where both disjunctivism and disjunctionism are false. After all, in this case we are to imagine that

disjunctivism is wrong to question the inference from (i) to (ii), and disjunctionism is wrong to question the

inference from (ii) to (iii).

Nothing about disjunctionism requires granting that the inference from (i) to (ii) is correct, that is,

the disjunctionist could agree with the disjunctivist in questioning this step in the radical

underdetermination argument. Suppose, in the mailbox example, the materialist is in a good case and

disjunctivists are correct: the skeptic is wrong to think that materialists’ perception does not supply her with

reason to believe there is a material mailbox simply because it is subjectively indistinguishable from bad

cases. But it seems then that for the disjunctionist, perception will also supply a reason to believe the

mailbox disjunction, since the disjunction includes one good case. So, disjunctivism and disjunctionism are

co-possible.

Now it may be objected that even if they are co-possible, disjunctionism would be theoretically

gratuitous in this case, since the radical skeptic’s critique is neutralized by disjunctivism. Perhaps this is so.

I will not weigh in on this issue here. As noted above, my limited aim here is to show that the two doctrines

are logically independent. I do not make the further claim that neither is theoretically gratuitous in light of

the other. So, it may well be that if one endorses disjunctivism the need for disjunctionism is obviated. 42 As

indicated, a detailed comparison of the two theories is beyond the scope of this work.

Concluding Remarks

It might be protested by entitlement strategists that any claim by EWD to answer skepticism is a bit like

claiming to have won the war by going over to the enemy’s side. After all, saying that we cannot know

which of the disjuncts is true sounds an awful lot like skepticism.

42 I owe this point to an anonymous referee. 30

To assess this line of thought, let us start with a brief recap of the dialectic: In the first part of this

paper, it was argued that 1MWH is not merely underdetermined, but radically underdetermined, because

there is a dogmatic defeater for 1MWH, namely, it is more epistemically likely that some other hypothesis

about the cause of our sensory experience is true. According to entitlement’s own standards for entitlement,

this means that 1MWH (and other external world hypotheses) cannot be accepted as a hinge proposition.

Second, as argued in section 7, it is simply a false dilemma that conceding evidential poverty requires us to

either adopt the entitlement strategy or suffer the catastrophic epistemic consequence of having to

completely ‘distrust perception’ or be mired in ‘cognitive paralysis.’ Such a sweeping skepticism would

deny that we have justified belief about even the mailbox disjunction. So EWD lies between two extremes.

On the one hand, it claims contra the entitlement strategy, that we are not justified in believing particular

hinge metaphysical hypotheses, or particular disjuncts about everyday matters. On the other hand, EWD

allows that we may have justified belief or knowledge about the disjunctions themselves, contra the more

sweeping skepticism suggested by the ideas of cognitive paralysis or distrusting perception.

I want to offer here a very tentative suggestion as to why the (wrong) idea of cognitive paralysis or

distrusting perception might seem compelling when giving up justified belief about particular hinge

propositions about the external world. To do this, let me first address the problem that living according to

EWD would seem to carry a heavy burden in terms of verbosity. As we saw above, an EWD proponent

must use the mailbox disjunction to refer to the object in the path of one’s companions. It is easy to imagine

how quickly it would become very tiresome to refer to objects in one’s environment via disjunction. If your

spouse, a dogmatist about 1MWH, asks where his keys are, you might reply, “I do not know where your

keys are. However, your material keys, or your immaterial keys, or your virtual keys are on the material,

immaterial, or virtual kitchen counter.” If speaking in such a manner is the only option, then EWD

proponents are likely to lead very solitary lives.

However, imagine you have an EWD ‘coming-out’ party, where you gather your friends and family

and publicly announce the following:

I am going cold turkey; I’m swearing off dogmatic metaphysics. I believe there is nothing

evidentially special about 1MWH that favors it over competitor hypotheses. Sometimes, when

speaking with others, I will allow myself liberties. I will allow myself to say, for example, “the ball

31

is under the car” to the kids playing street hockey. But when I say such things, I will mean “the

material ball is under the material car,” or “the immaterial ball is under the immaterial car,” or “the

virtual ball is under the virtual car.” Those of you who know me will know this is what I mean as a

result of listening to this public avowal. Strangers, such as the kids playing hockey, may mistake me

for a dogmatic metaphysician. But I can live with their scorn for the sake of Gricean verbal

efficiency.

This is a bit over the top, but the basic idea seems sound enough: even if our everyday vocabulary is

semantically loaded in favor of a particular hypothesis (e.g., the material world hypothesis), semantic

reform is at least an option.

Returning now to the question of why cognitive paralysis might seem like a consequence of

rejecting hinge propositions, my tentative explanation is that our everyday language may be semantically

loaded in terms of a preferred metaphysical hypothesis, e.g., the material world hypothesis.43 If there were

no alternative but to use our everyday language committed to something like 1MWH to describe the

experience of our environment—think of this as being ‘semantically locked-in’—then perhaps we really

would have to distrust perception and face cognitive paralysis. As noted, disjunction and various qualifiers,

e.g., ‘immaterial’, ‘virtual’, ‘dream’ etc., allow us to neutralize the metaphysical commitments of our

language, hence we are not semantically locked-in. We may reject the stark choice offered by the

entitlement strategy between accepting a particular metaphysical hypothesis of our current language, and

accepting the sweeping skepticism suggested by completely distrusting perception. 43 The idea that what we mean by some of our terms having metaphysical implications is suggested by Moore:

If I say of anything which I am perceiving, 'That is a soap-bubble', I am, it seems to me, certainly implying that

there would be no contradiction in asserting that it existed before I perceived it and that it will continue to

exist, even if I cease to perceive it. This seems to me to be part of what is meant by saying that it is a real soap-

bubble, as distinguished, for instance, from an hallucination of a soap-bubble…. (1993, 164-165).

It is an interesting question whether our everyday vocabulary really is semantically loaded in the way that Moore claims. I won’t

pursue this question here but concede it for the sake of the argument. I say ‘concede’ because if our language is less semantically

loaded than what Moore seems to indicate, then it may well be that there is less semantic reform necessary to endorse EWD. 32

It is worth noting that I have not argued for skeptical dogmatism or EWD directly, since the

arguments presented here depend on the un-argued assumption of evidential poverty. Still, for those who

would like to maintain dogmatism about 1MWH to the exclusion of other metaphysical hypotheses, the

lesson here is not to concede evidential poverty in the first instance, or perhaps adopt a different conception

of hinge propositions (such as those mentioned at the end of section 3). On the other hand, to echo

Berkeley, EWD is at least suggestive that the rest of humankind may not miss dogmatic metaphysics about

particular world hypotheses all that much.44

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