Wittgensteinian Hinge Epistemology and Deep Disagreement

Abstract

Deep disagreements concern our most basic and fundamental commitments. Such disagreements seem to be problematic because they appear to manifest epistemic incommensurability in our epistemic systems, and thereby lead to epistemic relativism. This problem is confronted via consideration of a Wittgensteinian hinge epistemology. On the face of it, this proposal exacerbates the problem of deep disagreements by granting that our most fundamental commitments are essentially arationally held. It is argued, however, that a hinge epistemology, properly understood, does not licence epistemic incommensurability or epistemic relativism at all. On the contrary, such an epistemology in fact shows us how to rationally respond to deep disagreements. It is claimed that if we can resist these consequences even from the perspective of a hinge epistemology, then we should be very suspicious of the idea that deep disagreements in general are as epistemologically problematic as has been widely supposed.

1 The Problem of Deep Disagreements

Much of the literature on the epistemology of disagreement is focussed on cases of epistemic peer disagreement.¹ The question raised by such cases is how one should respond when faced with disagreements of this kind. In particular, should one downgrade one’s confidence in one’s belief as a result, or can one legitimately retain the same level of confidence regardless (or is there a third option)? Although epistemic peer disagreements are undoubtedly philosophically interesting, they are very different from the kinds of disagreement that concern us here. This is because in normal cases of epistemic peer disagreement the issue over which the two parties are disagreeing is relatively shallow, in the sense that very little of practical consequence rides upon it. Take, for example, the familiar case of epistemic peer disagreement from the literature that concerns what the split on the restaurant bill amounts to. Although one would ideally like to resolve an issue like this in an equitable and rational manner, it is hardly the end of the world if one ends up walking away with the matter unresolved (e.g., if one elects to go along with one’s epistemic peer’s assessment of the split, which you dispute, in order for an easy life).

The cases that we will be looking at, in contrast, are not shallow in this sense as they concern the most basic commitments on the parts of the disagreeing subjects. These are the kinds of commitments that reflect our ways of seeing the world, at a most fundamental level, and in doing so often reflect our deeply held values. Call disagreements of this kind deep disagreements.² The obvious examples of this kind are religious disagreements, or at least disagreements between those who are religious and those who are not. But as we will see there can be other disagreements of this fundamental kind, beyond the religious, such as basic political or ethical disagreements.

Deep disagreements are more problematic than their shallow counterparts since often the two sides do not even agree on what counts as relevant evidence or reasons as regards the subject matter in question. That is, such cases seem to involve a kind of epistemic incommensurability, in that the two sides occupy distinct epistemic systems that have their own internal epistemic standards. This means that each epistemic system is generating an apparent positive epistemic standing, albeit in direct opposition to each other. Worse, each epistemic system doesn’t recognise the epistemic standing generated by the other epistemic system. This generates a stand-off, since how is one to rationally evaluate a dispute like this where there is not a shared system of epistemic evaluation? Deep disagreement thus seems to inexorably lead to a kind of epistemic relativism, whereby the dispute in question cannot even in principle be resolved on a purely epistemic basis, and hence we must instead resort to other means (such as big sticks, or worse).

While I can see the prima facie force of this line of argument, I am in fact sceptical that deep disagreements do collapse into epistemic relativism in this fashion.³ Rather than make a general case for this scepticism, I will be approaching the matter rather differently. It is commonly held that a Wittgensteinian hinge epistemology, of the sort that Wittgenstein sets out in his final notebooks (published as On Certainty [=OC]), would exacerbate the problem of deep disagreements just set out.⁴ We will explore the reasons why philosophers make this claim in a moment. My goal, however, will be to show that a Wittgensteinian epistemology, properly understood, not only does not intensify the problem of deep disagreements, but actually shows us how such apparently intractable disputes can be resolved in a fully rational manner, albeit in a ‘side-on’ fashion that I will explain. If it’s true that even a Wittgensteinian epistemology can accommodate deep disagreements without allowing them to collapse into epistemic relativism, then that should, I hope, go some considerable way towards showing that the threat of epistemic relativism in this regard is significantly overstated.

2 Wittgensteinian Hinge Epistemology

What Wittgenstein offers us in his final notebooks is nothing less than a radically new way of understanding the structure of rational evaluation. At the heart of this proposal is the idea that all rational evaluation takes place relative to a backdrop of basic arational commitments, commonly known as hinges (OC, § 141–143). These hinge commitments are essentially arational because the fact that they need to be in place in order for rational evaluations to occur means that they cannot be rationally evaluated themselves (hence the ‘hinge’ metaphor: the hinges must stay in place in order the ‘door’ of rational evaluation to turn).

Wittgenstein offers a range of instances of hinge commitments, where what sets them apart from other kinds of commitments is often just how ordinary and mundane they are. Here are some examples: that one has hands (OC, § 125), that one is speaking one’s native language (OC, 158), that one’s name is such-and-such (OC, § 328), that one has never been to the moon (OC, § 337), and so on. The hinge commitments have a number of interesting properties. I will here focus on four core properties that are particularly relevant for our purposes.⁵

First, we are optimally certain of them, as they constitute the backdrop of certainty that is needed in order for rational evaluations to occur. On the Wittgensteinian picture, belief and doubt, and other moves in the space of reasons, presuppose a prior backdrop of certainty that manifests itself in a range of optimally certain hinge commitments (e.g., OC, § 115).

Second, our commitment to the hinges is not optional, much less something over which we can maintain any kind of intellectual distance (i.e., they are not assumptions or hypotheses). It is rather an all-out commitment that is visceral, “animal” (OC, § 359). As Wittgenstein puts it at one juncture, “it is there—like our life” (OC, § 559; cf., OC, § 344).

Third, our hinge commitments are ordinarily tacit, in that they are rarely made explicit in our normal rational activities, much less do we become of aware of them qua hinge commitments. As Wittgenstein puts it, “they lie apart from the route travelled by inquiry” (OC, § 88). Relatedly, our hinge commitments manifest themselves most fundamentally not in what we say but rather in what we do. That is, it is our manner of acting that manifests the certainty that constitutes our hinge commitments.⁶

Fourth, our hinge commitments are not responsive to rational considerations (not directly anyway—the import of this caveat will be explained below). Given the point just made about how they are tacit in ordinary inquiries, it follows that they are rarely engaged with from a rational point of view anyway, and so this feature of our hinge commitments is also normally hidden from view. But even in unusual contexts (such as when doing philosophy) where one becomes aware of one’s fundamental everyday commitments qua hinge commitments, and thereby comes to recognise their groundless nature, this has no effect at all on our certainty in this regard. In coming to realise that one has no rational basis for thinking that one has hands, for example, one is not thereby led to actually doubt that one has hands (i.e., as opposed to merely going through the superficial motions of a kind of ‘faux-doubt’). Indeed, that one does not doubt this is manifest in how one continues to act just as before.⁷

3 Wittgensteinian Hinge Epistemology and Deep Disagreements

With this Wittgensteinian account of hinge commitments in place, one can see how it might be thought to exacerbate the problem of deep disagreements. To begin with, we now have identified at least a sub-class of deep disagreements, which is when two opposing camps confront one another with differing hinge commitments. This is surely possible on the Wittgensteinian conception. For example, someone raised in a religious community where God’s existence is taken as an obvious fact of life is likely to have religious hinge commitments that would be alien to someone raised in a largely secular environment.⁸ Or consider someone raised in a deeply politically conservative social milieu, as opposed to someone brought up in a commune exclusively populated by people of a left-wing political persuasion. Clearly, one would expect this to lead to individuals with very different hinge commitments regarding core political matters.

So there can be divergence in hinge commitments across people. Given the nature of our hinge commitments, it seems almost definitional that a clash of hinge commitments is a deep disagreement. Moreover, since one’s hinge commitments are essentially arationally held, it appears to follow that deep disagreements of this kind cannot be rationally resolved. Indeed, since it is one’s hinge commitments that determine the nature of one’s rational evaluations, we also seem to get the epistemic incommensurability claim noted above by default. After all, for each camp different hinge claims will stand fast, and hence they will undertake different local rational evaluations as a result, each relative to their own distinctive set of hinge commitments. For those with religious hinge commitments, for example, the local rational evaluations will always be such as to not come into conflict with those religious hinges, in contrast to those who lack such religious conviction. It thus seems as if each is occupying their own closed epistemic realm of rational evaluation, completely disconnected from the other. And once we have epistemic incommensurability in play it seems but a small step to get full-blown epistemic relativism. For isn’t that precisely where we are at, in that what it is rational for one group to believe, relative to their hinge commitments, is different from (indeed, in opposition to) what it is rational for the other group to believe, relative to their hinge commitments? Isn’t that just epistemic relativism?⁹

I think Wittgenstein was genuinely concerned about this kind of line of thinking, and where it would take us. Indeed, I have claimed elsewhere that the inspiration for the main line of reasoning in OC comes from the work of Newman (1979 [1870]). Newman’s interest, however, was specifically in a certain way of defending the rationality of religious belief. In particular, he mounted a kind of ‘parity argument’, of the sort more recently popularised by proponents of reformed epistemology. Such arguments maintain that so long as we hold religious belief to the same epistemic standards as paradigm kinds of non-religious belief, then there is no case for thinking the former to be in any way epistemically deficient.¹⁰ Normally, however, these parity arguments proceed by showing how religious belief has all the same positive epistemic credentials as the corresponding paradigm kind of non-religious belief. Newman’s claim, in contrast, was rather different. He conceded that religious belief has, at its core, essentially arational religious commitments. But he argued that this does not demonstrate that there is anything epistemically amiss with religious belief, since all belief, religious or otherwise, by its nature has arational commitments at its core. Accordingly, if non-religious belief is held to be epistemologically unproblematic, then the same verdict should apply to religious belief as well.

There is no doubt that Wittgenstein was very familiar with Newman’s work, and that he took his ideas very seriously. Indeed, he actually mentions Newman at the very start of OC (§ 1), which is unusual in itself, and also makes use of an example that was originally due to Newman (1979 [1870], p. 177).¹¹ With this in mind, we can plausibly read OC as Wittgenstein working through Newman’s ideas with a more general application than just the rationality of religious belief in mind. In particular, I think we can interpret OC as attempting to make sense of the idea of hinge commitments in general, and in the process understand why this idea doesn’t collapse either into a form of scepticism by default or else a form of epistemic relativism. On the latter front, the concern that Wittgenstein comes to again and again is what happens when, in the face of deep disagreements involving hinge commitments, reasons give out and we are left only with persuasion. Here, for example, is a key passage in this regard:

Where two principles really do meet which cannot be reconciled with one another, then each man declares the other a fool and heretic.

I said I would ‘combat’ the other man,—but wouldn’t I give him reasons? Certainly; but how far do they go? At the end of reasons comes persuasion. (Think what happens when missionaries convert natives.) (OC, §§ 611–612, italics in original; cf., OC, § 262)

The upshot, of course, is that what persuasion involves in this regard is epistemically problematic. Since such persuasion cannot, it seems, be a rational process, it must employ other means, such as coercion, bribery, and so forth. And that is, from a rational point of view at least (if not simply generally), a worrying way for deep disagreements to get resolved.

4 Wittgensteinian Hinge Epistemology, Properly Understood

Although I grant that the line of reasoning that takes us from a Wittgensteinian hinge epistemology to epistemic incommensurability and epistemic relativism regarding deep disagreements is superficially plausible, I also think that it can be resisted. What is key is a proper understanding of hinge epistemology and what it involves, and in particular how best to understand the nature of our hinge commitments.

Our hinge commitments can superficially seem to be a heterogeneous bunch. As noted above, they appear to vary in terms of one’s geography (e.g., one’s native language), one’s cultural epoch (e.g., whether one has been to the moon), one’s personal circumstances (e.g., whether one has lost one’s hands), and so on. This has led many commentators to conclude that there is no common element to our hinge commitments, and hence to emphasise instead their variability.¹² But this is a mistake, in that the differences between our hinge commitments are purely superficial.

What all of our hinge commitments have in common is that they are manifestations of an overarching commitment that we are not radically and fundamentally in error in our beliefs. I refer to this as the über hinge commitment.¹³ The idea is that, given the über hinge commitment and one’s wider set of beliefs, this general commitment will manifest itself as a commitment towards a range of specific propositions. Exactly which propositions will depend on one’s set of beliefs. So, for example, if one’s native language is Chinese, then it will manifest itself in a specific hinge commitment that one is speaking Chinese, while if one’s native language is English, then it will manifest itself in a specific hinge commitment that one is speaking English, and so on. Thus, the apparent ‘geographical’ differences in one’s hinge commitments are entirely superficial, in that it is essentially the same general hinge commitment that is manifesting itself (i.e., a hinge commitment regarding what one’s native language is). The same goes for our other hinge commitments that seem to manifest different contents. For example, that a hinge commitment for me is that my name is DHP, while a hinge commitment for you is that your name is such-and-such, doesn’t reveal anything inherently relative about the nature of our hinge commitment, but rather just shows how essentially the same hinge commitment can manifest itself with regard to slightly different contents.

The role that the über hinge commitment plays also explains how a commitment to a certain proposition can be at one time a hinge commitment and at other times an ordinary belief. So, for example, while in ordinary circumstances it is a hinge commitment that one has hands, clearly this is not the case if one is coming around in hospital after a serious car accident. Now it makes perfect sense to ground one’s belief that one has hands on what one sees before one. [Whereas this would make no sense at all in normal circumstances, as one is no more certain of one’s eyesight than that one has hands (OC, § 125)]. The crucial point is that one’s wider set of beliefs has changed such that one’s über hinge commitment no longer manifests itself as a specific hinge commitment towards this proposition.

Or consider the example noted above that one has never been to the moon. This may well be a hinge commitment for us, but one can easily imagine a future generation that has a very different set of beliefs about how common space travel is, and which accordingly doesn’t treat this as a hinge commitment. For them, the issue of whether they have been to the moon might be akin to me wondering whether I have ever been to Norwich (I’m fairly certain I haven’t, but it’s quite possible for an Englishman to have been to a city like Norwich without realising—for example, we might have passed through there on a childhood family holiday). As before, what ensures that what is a hinge commitment for one epoch but not for another is the different set of beliefs in play, such that one’s über hinge commitment no longer manifests itself as a specific hinge commitment towards this proposition.

Once we understand that our specific hinge commitments are merely manifesting the über hinge commitment, then we have an explanation for why our hinge commitments have the properties noted above. For example, it is hardly surprising that one cannot have a rational basis for the über hinge commitment, and hence that certainty in this regard is part of the backdrop that enables rational evaluations to occur. For how would one rationally ground such a commitment, without blatant bootstrapping? Moreover, it is very plausible that certainty in such a commitment is something that one ‘swallows down’ as part of the specific things that one is taught, and hence that the über hinge commitment is effectively hidden from view in ordinary contexts of inquiry. And so on. The point is that once we understand the relationship between the über hinge commitment and our more specific hinge commitments, then we also understand how the properties of the former become manifested in the latter.¹⁴

Now that it is clear that the apparent variability of our hinge commitments is merely superficial, we can get a handle on how the divergence in our hinge commitments is not nearly so radical as might have been initially thought. So, for example, although someone raised in China, with a different name (and so on), will have hinge commitments with different contents to mine, once we abstract from these contextual differences we are effectively sharing the same hinge commitments. There is thus no rationale on this score at least for epistemic incommensurability, as although the contents of our hinge commitments differ, these differences are purely superficial, and provide no basis for thinking that, for example, we do not have shared standards of evidence, or lack shared epistemic principles.

Interestingly, although the hinge metaphor is the one that stuck as regards Wittgenstein’s treatment of these special commitments, the other metaphors that he uses are perhaps more revealing this regard. The import of the metaphor of the hinge is just to emphasise the point that something needs to be in place—i.e., the backdrop of hinge certainty—for the ‘door’ of rational evaluation to turn. The thing about hinges, however, is that one can move them at will, and thereby change the way the door turns. As noted above, however, this not what Wittgenstein has in mind, as he wants to capture the sense in which our hinge commitments are completely non-optional. The other metaphors that Wittgenstein uses have none of this connotation of optionality. For example, Wittgenstein notes that our hinge commitments: constitute the “scaffolding” of our thoughts (OC, § 211); form the “foundations of our language-games” (OC, §§ 401–403); and represent the implicit “world-picture” from within which we inquire, the “inherited background against which [we] distinguish between true and false” (OC, §§ 94–95).

Perhaps the most revealing metaphor of all, however, is the ‘river-bed’ analogy that Wittgenstein offers in a famous set of passages:

It might be imagined that some propositions, of the form of empirical propositions, were hardened and functioned as channels for such empirical propositions as were not hardened but fluid; and that this relation altered with time, in that fluid propositions hardened, and hard ones became fluid.

The mythology may change back into a state of flux, the river-bed of thoughts may shift. But I distinguish between the movement of the waters on the river-bed and the shift of the bed itself; though there is not a sharp division of the one from the other.

But if someone were to say “So logic too is an empirical science” he would be wrong. Yet this is right: the same proposition may get treated at one time as something to test by experience, at another as a rule of testing.

And the bank of that river consists partly of hard rock, subject to no alteration or only to an imperceptible one, partly of sand, which now in one place now in another gets washed away, or deposited. (OC, §§ 96–99)

There are a number of interesting features of this metaphor. One such feature is how change in one’s hinge commitments is a gradual process that takes place over time, often imperceptibly. This accords with the point above concerning how the über hinge commitment generates our specific hinge commitments in concert with our wider set of beliefs, such that as one’s beliefs change, then so too, over time, can our specific hinge commitments change as well. (Think, for example, of the hinge commitment that one has never been to the moon).

Another feature is the suggestion of commonality in our hinge commitments. The idea is clearly that we are all being swept along this river collectively, rather than individually. This accords with other remarks that Wittgenstein makes in this regard. For example, he notes that:

In order to make a mistake, a man must already judge in conformity with mankind. (OC, § 156)

In particular, the idea seems to be that if there was too great a divergence in one’s hinge commitments, then that would prevent one from even being intelligible. Here is Wittgenstein:

The truth of my statements is the test of my understanding of these statements. That is to say: if I make certain false statements, it becomes uncertain whether I understand them. (OC, §§ 80–81)

Wittgenstein seems to be endorsing here the kind of holistic form of content externalism that was later defended by Davidson (1977, 1983). Davidson argued for a ‘principle of charity’ constraint on interpretation, such that one is required to interpret others such that their beliefs largely come out as true, on pain of being unable to make sense of the other person at all, and on this basis famously argued that “belief is in its nature veridical” (Davidson 1983, p. 146). The principle of charity was itself employed to block an incommensurability thesis, albeit at the level of content rather than epistemology. But the claim about content effectively acts as kind of base-level which limits the level of divergence in beliefs, and thus in hinge commitments, that subjects are allowed to have.¹⁵

The net effect is that the Wittgensteinian picture we are outlining does not allow radical divergences in one’s hinge commitments at all, at least when properly understood. Now this is not to deny that there could be significant differences in our hinge commitments—i.e., differences that are not merely superficial in the way just described. After all, as we noted earlier, we can imagine differences in the fundamental religious or political (or ethical etc.,) hinge commitments that subjects have. This would be a difference in hinge commitments that is not merely superficial, and where there are disagreements regarding these hinge commitments they would plausibly qualify as deep disagreements. But given the foregoing, it would follow that such divergences in hinge commitments will be only partial, in that agents who are so much as intelligible to each other will inevitably have overlapping hinge commitments. As we will see, this has important ramifications for how we understand deep disagreements on this view.

5 Wittgensteinian Hinge Epistemology and Deep Disagreements, Redux

We are now in a position to understand why a Wittgensteinian hinge epistemology, properly understood, does not lead to epistemic incommensurability, much less to epistemic relativism, and hence why it does not generate a particular problem for deep disagreements. Indeed, as we will see, hinge epistemology in fact gives us practical guidance on how to rationally resolve deep disagreements.

Let’s remind ourselves of what epistemic incommensurability is. Recall that this involves two completely closed epistemic systems confronting each other, such that there is no common epistemological ground on which to assess the dispute (no common ground in terms of what counts as acceptable evidence to resolve this dispute, for example). It is this claim that generates the troubling conclusion that there can, even in principle, be no rational way of resolving the dispute in question, and which in turn licences epistemic relativism. Note that epistemic incommensurability is different in kind, and not merely degree, from the claim that resolving deep disagreements may be practically speaking very difficult. This last claim, after all, far from being contentious, is obviously true. But nothing follows from this practical limitation on resolving deep disagreements in terms of epistemic relativism.

This last point is crucial, because once we have set-out a hinge epistemology correctly, then all we are left with is the weaker, uncontentious, claim about the practical difficulty of resolving deep disagreements. In particular, once we recognise the essentially overlapping nature of our hinge commitments, then it follows that there is no inherent reason why there cannot be rational resolutions of deep disagreements involving divergent hinge commitments. This is because even despite the divergent hinge commitments, there will also be lots of shared common ground, not just in terms of everyday beliefs but also in terms of shared hinge commitments. And that offers those who want to rationally resolve this disagreement lots to work with. Deep disagreements might be practically hard to resolve, but they need not be intractable.

Still, one might wonder how one would go about resolving such a dispute, given that one’s hinge commitments, while grounded in the overarching certainty that constitutes the über hinge commitment, are arationally held. The way that we have unpacked a hinge epistemology above offers us concrete guidance on this score. We noted above that one of the core properties of our hinge commitments is that they are not directly responsive to rational considerations. In particular, in becoming aware of their groundless nature one is not thereby led to actually doubt them (i.e., in any sense that would have a bearing on one’s actual behaviour). Crucially, however, that our hinge commitments are not directly responsive to rational considerations does not mean that they are completely unresponsive to rational considerations.

Indeed, we have already seen how our hinge commitments can alter over time, and in rational ways. One’s specific hinge commitments, remember, are simplify codifying, given one’s wider set of beliefs, one’s overarching über hinge commitment. Accordingly, as we saw above, as one’s beliefs change over time, so too does the specific hinge commitments that manifest one’s über hinge commitment. There is nothing in a Wittgensteinian hinge epistemology, however—or for that matter in the nature of deep disagreements more generally—which entails that the ordinary processes of belief change are not rational. We thus have a way of dealing with deep disagreements involving hinge commitments in a rational fashion, albeit in an indirect, and side-on fashion.¹⁶

The crux of the matter is that while it would be fruitless in the face of deep disagreement of this kind to try to change someone’s hinge commitments head-on, there will always be a rational way of engaging with the other party by looking to common ground (common beliefs, common hinges), and using that common ground to try to change their wider set of beliefs. If this is achieved, then over time one can change the other person’s hinge commitments. More precisely, as their wider set of beliefs changes, so too will the specific hinge commitments which manifest their über hinge commitment (which never changes).

Of course, the other person in this deep disagreement is open to adopt a similar strategy towards you, and in the process they might well convince you to change some of your beliefs, and hence some of your hinge commitments. I think this is an interesting consequence of approaching deep disagreement involving hinge commitments in this side-on fashion. If one restricts oneself merely to a head-on approach to the disagreement, then the scope for change, either in terms of the other’s person’s beliefs and hinge commitments or one’s own, is highly unlikely. But a side-on approach to these disagreements has the potential to open-up both parties to a change in views.

Any such change in either party’s hinge commitments will be inevitably slow, and there may well be all kinds of non-epistemic hurdles to change of this kind (perhaps, for example, some people are so psychologically wedded to their worldview that they simply will not allow their beliefs to change in the relevant respects). But remember that such practical hurdles to resolving deep disagreement are not what licenses epistemic relativism, but only the in principle epistemic incommensurability that was meant to follow from a Wittgensteinian hinge epistemology. Not only does this not follow from this view, but in fact this proposal highlights the way in which we should approach disagreements of this kind.¹⁷

6 Concluding Remarks

This is a good juncture to remind ourselves of the dialectical situation. We began with the prima facie epistemological challenge that deep disagreements pose, such that they seem to lead to epistemic incommensurability and, thereby, to epistemic relativism. We then argued that these consequences seem most obviously to follow if one embraces a Wittgensteinian hinge epistemology which grants that our most fundamental commitments—the very kinds of commitments that are at issue in deep disagreements—are essentially arationally held. We have seen, however, that far from licencing epistemic incommensurability and epistemic relativism, a Wittgensteinian hinge epistemology, properly understood, in fact gives us the tools to resist these consequences. This is because of two crucial features of a hinge epistemology: (i) the inevitable overlaps in our hinge commitments, and (ii) the relationship between the über hinge commitment and the specific hinge commitments which ensures that changes in one’s wider set of beliefs, which can be made in rational ways, can indirectly lead to changes in one’s specific hinge commitments. The first feature ensures that there is always some common epistemic ground, not only in terms of shared beliefs but also in terms of shared hinge commitments, which can provide the foundation for rational discourse between the two disagreeing parties. The second feature ensures that there is a rational process, albeit an indirect one, that enables one to change the other party’s beliefs and hinge commitments over time (and in the process expose oneself to rational change of one’s own beliefs and hinge commitments).

Where does this leave us with deep disagreements more generally? Well, insofar as we grant that a Wittgensteinian hinge epistemology brings the problem of deep disagreements into its sharpest relief, then the fact that this epistemology in fact doesn’t licence epistemic incommensurability or epistemic relativism should surely give us pause to wonder whether there is a ‘deep’ problem of deep disagreements. Indeed, we can put this point in terms of a dilemma. On the one hand, insofar as all deep disagreements are just disagreements involving hinge commitments, then the foregoing demonstrates that deep disagreements do not have the unwelcome epistemic consequences that have been advertised. On the other hand, there is the possibility that there is a sub-class of deep disagreements which don’t involve hinge commitments, and hence concerns fundamental commitments that aren’t held in an essentially arational manner. But in that case, why would we think that deep disagreements involving these commitments would lead to epistemic incommensurability and thus epistemic relativism anyway? At the very least, we are owed an argument as to why this might be so, and the prospects for such an argument do not look promising, given what we have seen with regard to how this difficulty is meant to play out in the supposedly more problematic case of a Wittgensteinian hinge epistemology.

The upshot is thus that the epistemic ‘problem’ of deep disagreements may not be as philosophically significant as many have supposed. Yes, resolving such disagreements can in practice be hard, perhaps even practically impossible. But the supposed epistemic problem that such disagreements is meant to pose doesn’t materialise when we focus in on the nature of deep disagreements, even when those disagreements involve essentially arational fundamental commitments.¹⁸