Philosophical
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RECENT WORK
MODAL EPISTEMOLOGY
The University of Liverpool
Introduction
The phrase ‘modal epistemology’ is most commonly used in two main ways
nowadays. In one, it concerns the epistemology of necessity and possibility. In
another, it refers to epistemologies which claim that for a belief to count as
knowledge there has to be a modal tie either between the belief and its being
true or between the cognitive habits of the believer and the believer’s beliefs
tending to be accurate.1 Though it would be interesting to consider their
inter-relations, this survey is of modal epistemology in the former, predominant sense.
Modality is a flourishing topic in logic, philosophy and computer science.
Work is dominated, though, by semantic, ontological, applied and, to a lesser
extent, syntactic concerns. Work on modal epistemology is thin on the
ground.2 The dearth of work on modal epistemology should be of special
concern to anyone who wants to uphold some form of realism about modality,
since it is epistemological concern that often motivates rejection of modal
realism.3 Another somewhat concerning fact is that recent writers on modal
epistemology have largely neglected to engage with each other, especially over
issues where there is disagreement in the literature. The same cannot be said
of work concerning modal logic, modal semantics and modal metaphysics: fairly
1. For a stimulating study of modal epistemologies in the second sense, see Lars Bo Gundersen,
Dispositional Theories of Knowledge (Acumen, 2003). George Bealer, ‘Modal Epistemology and the
Rationalist Renaissance’, in Tamar Szabó Gendler and John Hawthorne (eds.), Conceivability
and Possibility (Oxford University Press, 2002), pp. 71–125, p. 71 relates three senses of ‘modal
epistemology’, concerning (i) knowledge of the necessary and the possible; (ii) investigation
into what knowledge is possible and (iii) “the intersection of the first two: the theory of possible
modal knowledge—that is, of what modal knowledge is possible”. I cannot report having seen
any other occurrence of usage (ii) in the literature. It seems to me that looking into (i) involves
the others, but anyhow I don’t here take the trouble to be quite as particular as Bealer.
2. Compare Peter van Inwagen, ‘Modal Epistemology’, Philosophical Studies, 92 (1998), pp. 67–84,
p. 75; and John Divers, Possible Worlds (Routledge, 2002), p. 164.
3. If George Molnar, Powers: An Essay in Ontology (Oxford University Press, 2003), p. 124 is right
that anti-realism about immanent modality leads to a more thoroughgoing anti-realism, then
the need for a modal epistemology becomes even more pressing.
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widespread engagement with one’s peers is the order of the day in these fields.
One cannot help but suspect that the relative lack of both industry and progress in modal epistemology may partly be due to the lack of such engagement.
The onus is upon you to provide an epistemology of the modal if and only
if you are a semantic realist about modality. For the sake of this discussion,
I presume an affirmative answer to the question of whether we should be
semantic realists about the modal. What sort of epistemology does semantic
realism require? What relationships obtain between the modal, the a priori
and the empirical?
Modal knowledge is a paradigmatic example of a form of knowledge apt
for classification as fundamentally a priori. Kripkean necessity a posteriori
does not undermine this tenet, since Kripke takes each instance of necessary
a posteriori knowledge to be derived, via modus ponens, from a necessary a
priori major premise and an empirical minor premise.4 For example, we infer
that necessarily, water is H2O from the empirical premise that water’s chemical formula is H2O and the a priori premise that if a chemical stuff has a
given chemical formula then it has that formula of necessity.5
Recent approaches to the epistemology of the necessary a posteriori largely
emanate from the Kripkean model in one way or another. Colin McGinn and
Christopher Peacocke both try to show that the modal aspect of all modal
knowledge boils down to a priori knowledge and both, though particularly
Peacocke, address the question of what principles are fit to feature as major
premises in arguments to necessity a posteriori.6
George Bealer develops the Kripkean model by arguing that rationalism is
limited to the modal major premise, that intuitions (so prominent in Kripke)
carry evidential weight and that only a rationalist account of the ultimate
principles fit to feature as modal major premises is adequate.7
Alan Sidelle appropriates the Kripkean model, giving it an ontologically
anti-realist twist. He holds that the major premise is analytic and that analyticity is a matter of stipulation.8
4. Saul A. Kripke, ‘Identity and Necessity’, in Milton K. Munitz (ed.) Identity and Necessity (New
York University Press, 1971), pp. 135 – 64, p. 153. For discussion, see Jonathan Dancy, An
Introduction to Contemporary Epistemology (Blackwell, 1985), pp. 219–21; George Bealer, ‘The
Limits of Scientific Essentialism’, Philosophical Perspectives, 1 (1987), pp. 289–365, pp. 292, 300;
Bob Hale, ‘Modality’, in Bob Hale and Crispin Wright (eds.), A Companion to the Philosophy of
Language (Blackwell, 1996), pp. 487–514, p. 492; Christopher Peacocke, Being Known (Oxford
University Press, 1999), p. 41; Crawford L. Elder, Real Natures and Familiar Objects (MIT Press,
2004), pp. 4 –7; and Bob Hale, ‘Knowledge of Possibility and of Necessity’, Proceedings of the
Aristotelian Society, 103 (2002), pp. 1–20, pp. 17–8.
5. The example follows Hale, ‘Modality’, p. 492.
6. Colin McGinn, ‘Modal Reality’, in R. Healey (ed.) Reduction, Time and Reality (Cambridge
University Press, 1981), pp 143–187; Peacocke, Being Known, Ch. 4, incorporating his ‘Metaphysical Necessity: Understanding, Truth and Epistemology’, Mind, 106 (1997), pp. 521–74.
7. See the aforementioned works by Bealer and his ‘The A Priori’, in John Greco and Ernest
Sosa (eds.) Blackwell Guide to Epistemology (Blackwell, 1998), pp. 243 –70. Bealer’s view contrasts
with that of Brian Ellis, Scientific Essentialism (Cambridge University Press, 2001), who rejects
rationalism.
8. Alan Sidelle, Necessity, Essence and Individuation: A Defense of Conventionalism (Cornell University
Press, 1989).
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Crawford Elder modifies the standard account by arguing that the major
premise is empirically known and that recognising necessity a posteriori does
not require commitment to trans-empirical modality.9
Semantic realism about modality includes moderate conventionalism and
ontological realism. Moderate conventionalism, a position subscribed to by
the logical positivists and revived, in a modified form, by Sidelle, holds that
modal truth is not grounded in extra-mental reality, but is a mere reflection
of our linguistic conventions.10
The ontological realist, meanwhile, holds one of the following positions:
Objectual modal realism: non-actual but real possible worlds are the ultimate
truthmakers for modal claims. (No worlds are modal in nature. Modal truth
at a world is relative to actual truth at other worlds.)
Non-objectual modal realism: non-actual possible worlds are not the ultimate
truthmakers for modal claims. Rather, necessity and possibility are immanent in the actual world. (The actual world is modal in nature. Non-actual
worlds either do not exist or are ontologically dependent upon modality.)
Empiricists and modal non-cognitivists typically view ontological realism of
either hue as ontologically profligate and epistemologically mysterious. Talk
of a peculiar, necessity-detecting faculty being a requirement of realism is
invoked partly to debunk realism. Often, such hostility to modal realism is
premised on a causal model of knowledge whereby we know an object by
means of its causal interaction with our cognitive faculties and the status of a
belief that p as knowledge is tied up with direct or indirect observational
evidence for p.
Conservativeness and the Analogy with Mathematics
Modality and mathematics are commonly held to be epistemologically akin
in that a causal model of knowledge can accommodate neither. The stock
response of the modal realist is ‘so much the worse for causal models of
knowledge’. The fault lies with the sparse epistemology, not the lavish ontology. As part of this response, the realist sometimes says something like the
following. ‘Look: we can’t know mathematical truths causally. We do know
mathematical truths. So, a causal model of knowledge is inadequate anyway.
We don’t need to worry, then, about the fact that modal knowledge can’t be
accounted for causally.’
The analogy with mathematics occurs in, among other places, the work of
Colin McGinn (a non-objectual modal realist) and David Lewis (the arch
9. Real Natures and Familiar Objects. See also ‘An Epistemological Defence of Realism About
Necessity’, Philosophical Quarterly, 42 (1992), pp. 317–36.
10. Against Sidelle’s view, see Stephen Yablo’s review, Philosophical Review, 101 (1992), pp. 878 –
81; and Elder, Real Natures and Familiar Objects, Ch. 1.
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objectual realist).11 At least on the surface, objectual modal realism looks more
epistemologically suspect than non-objectual realism, since we are in perceptual contact with the actual world but cannot be with non-actual worlds. If
modality is immanent in the actual world rather than transcending it, then,
as a matter at least of prima facie intuition, modality is less seriously epistemologically puzzling. It is striking that among the ontological realists it is the
non-objectual realists who have tended both to acknowledge the difficulty of
providing an epistemology for modality and risen to the challenge of attempting to do it, rather than just settling for the sort of rejoinder to the causal
epistemologist voiced by Lewis and summarised in the previous paragraph.12
It seems to me to be a central (though largely implicit) question in the
recent literature as to whether or not modality is empirically conservative. I
believe this notion to lack satisfactory definition in the literature, but the basic
idea is that modality is empirically conservative if and only if adding modalising to a (putatively) non-modal empirical theory would not alter the empirical
consequences of the theory. McGinn13 views modality as akin to mathematics
in being empirically conservative, while Peacocke14 views a commitment to
the conservativeness of the modal as desirable in a philosophy of modality.
McGinn employs the notion of conservativeness in characterising modality
as trans-empirical. He claims that modality is trans-empirical in the sense that
it is, though truth-apt, empirically conservative. He takes it to follow from this
that modality is also trans-empirical in the (I think separate) sense that,
though truth-apt, our knowledge of the modal truth could not be based on
direct observation, indirect observation or argument to the best explanation
of observed phenomena.
Peacocke is non-committal on whether modality is empirically conservative
but he agrees that modal knowledge could not be based on direct observation,
indirect observation or argument to the best explanation of observed phenomena. It seems, anyway, that endorsing conservativeness is neither necessary nor sufficient for commitment to modal rationalism. It is not sufficient,
because to claim that a discourse is empirically conservative does not (unlike
commitment to rationalism about its epistemic justification) involve commitment to its truth-aptness. It is not necessary, since the rationalist need not
reject what Peacocke calls a “partially modal conception of reality” associated
with one kind of semantic primitivism about modality to the effect that “there
is no relevant non-modal segment of discourse of which modal principles
might be a conservative extension”.15
11. McGinn, ‘Modal Reality’; David Lewis, On the Plurality of Worlds (Blackwell, 1986), pp. 108 –9.
12. Otavio Bueno and Scott Shalkowski, ‘A Plea for a Modal Realist Epistemology’, Acta Analytica,
15 (2000), pp. 175 – 93, complain about Lewis’s lack of provision of a positive epistemology
and question the legitimacy of the analogy with mathematics. For a more sympathetic discussion of Lewis, see Divers, Possible Worlds, Ch. 9.
13. ‘Modal Reality’, pp. 178– 82.
14. Being Known, p. 175.
15. Ibid. Peacocke regards commitment to the conservativeness of modality as not required by his
principle-based account of modality. It seems to me that a problem with the notion of
conservativeness, as it stands, is that it is not clear whether it requires that there is such a
non-modal segment.
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Though commitment to the trans-empirical status of modality, in the second sense I marked out, is apparently a sufficient condition for commitment
to rationalism, it is not a necessary one. In order to be a rationalist about the
modal, one need only claim that some modal truths are trans-empirical, not
that modality is always trans-empirical. Again, the consistency of rationalism
with a partially modal conception of reality bears this out.
Though they do not use the term, the anti-rationalists Elder, Ellis and
MisDeviC reject the thesis of conservativeness and the thesis of the transempirical status of modality.16 Elder is most explicit on this, holding both that
we can discover necessities by solely empirical means and that an essentialist
claim will issue in different empirical consequences from an unmodalised claim.
Ellis’s work, meanwhile, seems to suggest that the postulation of modality in
nature provides the best explanation of observed phenomena and of features
of the laws of nature. McGinn anticipated such a view, which is partly why
he took the trouble to argue for conservativeness. A modalised description of
an actual world phenomenon does not, thinks McGinn, add any predictive
content to a description expunged of the modality. Nor can observation, per
se, serve to justify a modal claim.
Whether or not the literature contains a perspicuous definition of the
notion of empirical conservativeness for modality, there is certainly a lack of
engagement among those who view (or hope to view) the modal as conservative and those who (without using the word or mentioning him) make claims
either explicitly or implicitly inconsistent with McGinn’s view.17
Conceiving, Intuiting and Possibility
The question of whether such psychological operations as conceiving and
intuiting serve as guides to possibility is a more overt, and more widely discussed, topic than that of the whether modality is empirically conservative
and/or trans-empirical. There is also the related question of whether the
stronger relationship of entailment ever holds between such propositions as:
x intuits that p
x conceives that p
and
It is possible that p.
16. See the works by Ellis and Elder cited above and Nenad MisDeviC, ‘Explaining Modal
Intuition’, Acta Analytica, 18 (2003), pp. 5– 41.
17. MisDeviC’s article is the only discussion I have found that engages with named parties from
both camps. The article, though containing numerous editing errors, is philosophically
worthwhile.
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There is an unavoidable air of stipulation to such discussions, since there is
no widespread agreement among philosophers as to what we mean by conceives
and intuits and the everyday notions are hopelessly imprecise.
It seems to me that the question of whether modality is trans-empirical is
prior to that of whether p’s being the intentional object of some psychological
operation either entails or serves as evidence that p. Surely, we only are only forced
to resort to such hazy appeal if we really cannot know the modal by (relatively
straightforward, less hazy) empirical means, whether direct or indirect.
Nevertheless, claims which would, if true, be genuinely informative can be
made about the relationship between the operations of our purported psychological faculties and possibility. Both traditionally and recently, the appeal to
the idea that p’s being the object of some such psychological operation serves
as evidence for the possibility that p has featured in both rationalist and
empiricist accounts of modal knowledge.
Stephen Yablo holds that my conceiving that p gives me defeasible grounds
for holding that it is possible that p.18 Colloquially, ‘conceivable’ just means
believable, whereas, in the technical sense, p is conceivable only if it seems
possible that p. ‘Seems’ here is taken in an intellectual sense. “Whatever you
find [philosophically] conceivable, you are prima facie entitled to regard as
metaphysically possible.”19 Philosophical conceivability does not entail believability. It’s conceivable that I should never have existed, but not believable
that I never have. Believability does not entail philosophical conceivability,
since, for example, neither “Goldbach’s conjecture nor its negation is conceivable in the relevant sense” though both, given our current epistemic situation,
are believable.20
Though Bealer rejects conceivability as a guide to possibility,21 his position
is rather analogous to Yablo’s except that Bealer holds that it is my intuiting
that p that gives me defeasible grounds for holding that it is possible that p. For
Bealer, when I intuit that p then it seems (in an intellectual sense) to me that p.
I detect three other strands in the literature concerning the relationship
between p’s being the object of a certain intention and it being possible that p.
Outright dismissal. According to Ellis, what we find conceivable is determined
not by the nature of reality, but by how our minds work. Modal reality is out
there, so we have no grounds for thinking that conceiving, intuiting or imagining that p gives us evidence that it is possible that p.22
Epistemic naturalism. In contrast to Ellis, MisDeviC holds that since our cognitive habits are as they are because they have been shaped by the natural
18. Stephen Yablo, ‘Is Conceivability a Guide to Possibility?’, Philosophy and Phenomenological
Research, 53 (1993), pp. 1– 42. (For related discussion, see Hale, ‘Knowledge of Possibility and
of Necessity’. Hale addresses this issue within the context of a discussion of the viability of
an asymmetrical approach to modal epistemology. Such an approach maintains the epistemic
priority of the necessary over the possible, or vice versa.)
19. Ibid., p. 34.
20. Ibid., p. 11.
21. ‘Modal Epistemology and the Rationalist Renaissance’, pp. 75–7.
22. Scientific Essentialism, e.g., pp. 54, 280.
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world over the course of evolution, we should not be surprised if it turns out
that we have modal intuitions which track the deep modal structure of reality.23
Conceivability entails possibility. Chalmers commits to probable entailment
between a kind of conceivability (in a technical sense I won’t explore) and
possibility.24
Two Sorts of Modal Knowledge
As a matter of orthodoxy, mathematical and logical truths, though necessary,
are taken to differ epistemologically from Kripkean necessities a posteriori.
First, our methods of arrival at knowledge of the (unmodalised) truths are
taken to differ. Mathematical and logical truths can be known directly and,
even when derived, never depend on an empirical premise. Necessities a
posteriori, as the standard post-Kripkean account has it, are always derived
rather than axiomatic and (at least typically) depend on some empirical
premise. Second, there is a difference between our knowledge of the modality
of mathematical and logical truths as against necessities a posteriori. Plausibly,
where p is a logical truth, knowing that p provides grounds, of itself, for
holding that p is necessary. In the case of a true statement that is necessary a
posteriori, knowledge of its truth does not, of itself, provide grounds for holding it necessary.
For ease of reference, and for want of a better way of doing things, I will
refer to those necessities commonly called ‘the necessary a posteriori’ as
‘hypothetically’ necessary, as opposed to the ‘categorical’ necessities of logic
and mathematics. The main reason for using the term ‘hypothetical’ necessity
is that, despite my earlier claim that modal knowledge is an archetypal candidate for classification as a priori, I do not wish to beg the question against
some recent thinkers who seek to reject the a priori but retain the modal.25 I
would be so doing if I referred to hypothetical necessity as the ‘necessary a
posteriori’, since such thinkers so deem all necessity (except, in at least one
case, analytic necessities).26 Still, I need some way of marking out the orthodox
distinction as a prerequisite for my discussion. In any case, the term ‘hypothetical’ seems apt in this context, since: (i) the objects of such necessities are
not necessary existents, as the Kripkean notion of weak necessity is precisely
intended to capture; (ii) we know such a necessity only if we know that the
antecedent of a given known conditional is true and have applied modus ponens.
It seems that the primary epistemological question for the semantic realist
is that of how we know the categorically necessary. On no going theory that
I have encountered is it denied that knowledge of the hypothetically necessary
23. ‘Explaining Modal Intuition’.
24. David J. Chalmers, ‘Does Conceivability Entail Possibility?’, in Gendler and Hawthorne
(eds.), Conceivability and Possibility, pp. 145–200, esp. pp. 194–5.
25. The thinkers are Ellis, Elder, and MisDeviC.
26. Ellis, Scientific Essentialism, views analytic necessities as true by convention and, I would hazard, trivially a priori, though he has it that we need not appeal to the a priori in accounting
for essentialist necessities pertaining to the objects and laws of the actual world.
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is dependent on knowledge of the categorically necessary (even if some would
have it that we can know the necessary without appeal to rationalism). Some
writers on modality don’t seem to address this relationship at all,27 but no-one,
as far as I know, voices such denial. There was a time, very recently, when it
could have been said that no contemporary essentialist questions the need for
the a priori in an account of how we know the necessary a posteriori but the
very recent writings of Ellis, Elder and MisDeviC change that.
Categorical Necessity
Partly in reaction to Lewis, semantic realists who reject objectual realism are
agreed that there should be a close connection between that which makes a
modal truth true and the means by which we come to know it. McGinn
describes this as a condition upon ontological imputations.28 Peacocke refers
to it as ‘the Integration Challenge’.29
Sidelle attempts such integration by arguing that all necessity stems from
categorical analytic necessity. The moderate conventionalist traditionally had
it that necessity and analyticity are co-extensive. Sidelle does not subscribe to
this view, holding that there are a posteriori necessities. However, he does hold
that all necessity boils down to analyticity, since the a posteriori necessities
owe their necessity (though not their truth) to the analyticity of the major
premises in modus ponens inferences to necessity a posteriori. Analyticity, in
turn, Sidelle holds to be a matter of convention.
Other recent semantic realists who have addressed the epistemology of
categorical necessity have mainly done so by appeal to rationalism. Modal
rationalisms certainly have a more prevalent and developed profile in the
literature than do their pro-modal but anti-rationalist rivals.
Bealer and Peacocke are among the leading exponents of modal rationalism. Both appeal to considerations concerning the possession conditions on
concepts, though this plays a more central and technically developed role in
Peacocke’s account than in Bealer’s. Intuition is the central notion in Bealer’s
rationalism.
On Peacocke’s account, a thinker’s a priori knowledge that p consists in
their cognitive competence in using the concepts employed in p. This will
encompass (at least covert) grasp of principles of possibility. These branch into
principles of possibility at the level of sense and principles, dubbed ‘constitutive principles of possibility’ at the level of extension. Such principles are
instances of the following principle:
Unified Modal Extension Principle. An assignment s is admissible
only if: for any concept C, the semantic value of C according to s is the
27. E.g., Ellis, Scientific Essentialism.
28. McGinn, ‘Modal Reality’, pp. 146–7.
29. Peacocke, Being Known, Ch. 1.
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result of applying the same rule as is applied in the determination of the
actual semantic value of C. (Being Known, p. 136)
Principles at the level of sense account for a priori truths of mathematics
and logic, while the constitutive principles of possibility underwrite modal
metaphysical knowledge in a wider sense.
Peacocke asserts, rather than argues for, such constitutive principles as that
where “P is a property which is an object x’s fundamental kind, then an
assignment is inadmissible if it counts the proposition x is P as false”,30 and
that an assignment is inadmissible if it breaches Kripkean doctrines on the
necessity of origin.31 There is an apparent lacuna in Peacocke’s account in
that it does not elaborate on how constitutive principles of possibility are
known.
Bealer’s modal epistemology seeks to provide a full articulation of the
acquisition of modal knowledge. The account encompasses the basic claims
fit to feature as major premises in arguments to hypothetical necessity. Such
claims are ultimately justified by rational intuition. Intuition is not some
strange cognitive faculty. “To have an intuition that A is just for it to seem to
you that A” and such “seeming is intellectual, not sensory or introspective (or
imaginative)”.32 Intuitions are either “noninferential beliefs regarding the
applicability of a concept to a hypothetical case” or “mental states having a
strong modal tie” with such beliefs.33 This, in turn, requires an explanation
of why intuitions have ‘evidential weight’.34 He initiates his account by distinguishing, without suggesting that the divisions are hard and fast, between
naturalistic, category and content concepts:
Naturalistic concepts . . . include, for example, the concepts of water, heat,
gold, lemon, arthritis, beech, elm and so forth. . . . Examples of category
concepts are the concepts of stuff, compositional stuff, functional stuff,
substance, quality, quantity, action, artificial, natural, cause, reason, person,
etc. Examples of content concepts are familiar phenomenal qualities (pain,
itching, tingling-sensation, etc.) and basic mental relations (knowing, perceiving, deciding, loving, etc.).35
Naturalistic intuitions have evidential weight insofar as they are instances
(albeit empirically informed instances) of category/content intuitions that do
Ibid., p. 145, after the thought of David Wiggins, Sameness and Substance (Blackwell, 1980).
Ibid., pp. 145–6, after Saul Kripke, Naming and Necessity (Blackwell, 1980).
Bealer, ‘The A Priori’, p. 247.
‘The Limits of Scientific Essentialism’, p. 300. (Bealer unites the two forms of modal epistemology distinguished in my first paragraph.) ‘The A Priori’, p. 247 inclines away from the
former partly on the basis that intuition, unlike belief, is a form of seeming. See also ‘Modal
Epistemology and the Rationalist Renaissance’, p. 73 for differences between intuition, imagination and belief.
34. On this dialectic, see ‘The Limits of Scientific Essentialism’, pp. 300 –2. Playing devil’s
advocate, Bealer asks why intuitions should be any more weighty than gamblers’ hunches.
35. ‘The Limits of Scientific Essentialism’, p. 295. See also ‘Modal Epistemology and the Rationalist Renaissance’, p. 107.
30.
31.
32.
33.
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not employ naturalistic concepts. The latter intuitions, when correct, provide
modal knowledge fit for input as major premises in arguments to necessity a
posteriori. For example, the intuition (supposing it correct) that nothing other
than H2O counts as water derives its legitimacy from the empirical knowledge
that paradigm samples of water have the chemical formula H2O, together
with the a priori category intuition that “If paradigm samples of a compositional stuff have a certain complex composition, then items lacking that composition would not qualify as samples of the compositional stuff ”.36 Scientific
essentialism depends on intuitions counting as evidence; naturalistic intuitions
counting as evidence depends on non-naturalistic intuitions counting as
evidence; non-naturalistic intuitions counting as evidence depends on there
being “an autonomous level of category and content concepts, determinate
possession of which must be explained in a traditional, noncausal way and
theoretical knowledge of which may be obtained absolutely a priori”.37 So,
scientific essentialism depends on a form of rationalism. By the lights of
Bealer’s moderate rationalism, there is a modal tie between our intuitions and
the truth. Necessarily, when a person possesses a concept then in (at least)
most cases in which they are to make a non-inferential judgement about
whether or not that concept applies to an elementary hypothetical case, their
judgement will coincide with the truth.38 Since an intuition is closely akin to
such a judgement, intuitions have evidential worth.39 We can see, then, why
Bealer calls his epistemologies of the modal and the a priori ‘modal reliabilism’ and that, in appealing to conditions constitutive of the full possession of
concepts, Bealer and Peacocke are kindred epistemologists.40 For Bealer, a
given intuition is not necessarily primitively compelling. Rather, the outcome
of rational intuition may be arrived at via a kind of reflective equilibrium or
dialectical weighing of intuitions.
Hypothetical Necessity
As far as I know, no writer in the recent literature is a rationalist about
hypothetical necessity in the sense of believing that we know hypothetical
necessities independently of experience. Rather, the debate about the status
of the modal major premises in modus ponens arguments to hypothetical necessity is where the anti-rationalists take the action to be. In this, I agree: the
story does not end there, though. What of the epistemology for logical modality
and, in particular, for the modality attaching to principles that embody valid
36. ‘The Limits of Scientific Essentialism’, p. 304. Over pp. 310 – 4 Bealer extends modal intuitionism to the choice of basic principles in logic, metaphysics and mathematics.
37. Ibid., p. 309.
38. Ibid., p. 319; see ‘The A Priori’, p. 254 for a weaker claim.
39. Ibid., pp. 319–20.
40. Also, both are fallibilists about a priori justification and adopt dialectical, as opposed to
foundationalist, views of the role of a priori belief in total theory. See Bealer, ‘Modal Epistemology and the Rationalist Renaissance’, p. 74 and Peacocke, ‘How Are A Priori Truths
Possible?’, pp. 187–8, 192–3.
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patterns of deductive inference? The tendency among the anti-rationalists is
either to overlook the epistemological status of inferential principles altogether
or else to provide an account that is, in my view, sketchy and unconvincing.
Elder, for example, seems to think that if he has demonstrated that there is
an empirical test for distinguishing between the essential and the accidental
(be it concerning properties or concerning universal generalisations) he has
thereby refuted rationalism. On the contrary, the refutation of rationalism
requires a further stage: namely, an argument that logical knowledge does not
require the a priori. Among the anti-rationalist ontological realists about the
modal, only Ellis can be said to have really addressed this task and no-one
has done so very recently.41 Basically, his strategy was to adopt a form of
psychologism according to which logical laws are laws of thought and akin to
laws of physics insofar as they are abstractions from actual phenomena. It is
highly plausible that one has to be a realist about logic if one wants to be a
realist about the modal. On Ellis’s onetime account, it would appear that in
order to be a realist about logic one has to be a realist about laws of nature.
I take that to be an unfortunate consequence.42
Summary
The predominant tendency among ontological realists about the modal has
been to respond to epistemologically motivated critics of realism not by supplying a detailed epistemology but by adverting to the superiority, qua ontology, of their own position over that of their critics. Even McGinn’s position
has this basic form,43 though he has done more than most to try to explain
why modality is epistemologically problematic and what is at stake in debates
about its epistemological status.
Nevertheless, as we have seen, there has been a recent growth in interest
among ontological realists in providing a positive epistemology for the modal,
with theories being advanced from a rationalist camp and a camp hostile to
rationalism. Let’s hope that greater engagement will occur among writers
both within and between these camps. If it does, we can perhaps expect
greater progress in the project of providing an epistemology for modality.
41. Brian Ellis, Rational Belief Systems (Blackwell, 1979).
42. In Scientific Essentialism, Ellis seems to seek to combine conventionalism about de dicto modality
with realism about de re modality. For reasons I can’t go into here, I don’t see how this
combination can work.
43. As well as ‘Modal Reality’, see his Logical Properties (Oxford University Press, 2000), in which
he takes necessity to stand in the way of philosophical naturalism.
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© Blackwell Publishing Ltd. 2005