1. Introduction
Today, transcendental arguments (henceforth ‘TAs’) are usually viewed with the same nostalgia and estrangement with which we encounter an ancient temple from a distant time and culture: although we feel respect for its grand design and metaphysical aspiration, we also sense it to have been superseded by history, to ultimately express vain hopes and empty imaginations. For scientific progress has sobered us up to a disenchanted world in which the deities of old have never existed. The same can be said for the promise of world-directed TAs to deliver insights into ‘synthetic a priori’ propositions about how the world must be in order for thought or experience to be possible. Such TAs, for example, paradigmatically those formulated in Strawson’s Individuals (1959), seem too grand: they would serve as an epistemological bed-rock against skepticism and give us the definitive metaphysical verdict on our manifest image of the world, with the by-product of showing which elements of our conceptual scheme are immune to reduction or revision.
But why do we suppose that such ambitions are in vain—why, for that matter, are we so certain that an ancient temple is devoid of divinity? Maybe it is we who have fooled ourselves by thinking that visible things like decayed ruins and empty halls of worship could be used as a measure for divine presence. In a similar vein, so I will argue, we have misgauged the kind of truths that world-directed TAs can disclose about the world and the role they play in specifying the very yardstick of objectivity that we use in evaluating knowledge claims.
There is probably no philosopher more singularly responsible for the wide consensus that the claims of world-directed TAs are vain and outdated than Barry Stroud. His meta-epistemological skepticism about the prospects of world-directed TAs is widely seen as the be-all and end-all in this debate—although there have always been important dissenting voices like Brueckner (1983; 1984; 2010), Sacks (2000), and Stern (2007).1 Stroud concedes that TAs can show certain beliefs to have a special and fundamental status in our experience of the world, ourselves, and other agents, namely that they are invulnerable to revision or critique. But this is merely the work of ‘modest’ transcendental arguments which show that some beliefs are so fundamental to our conceptual scheme that they cannot be consistently denied. Stroud denies that any truths about the world could be derived from this and concludes that ‘ambitious’, world-directed TAs are not possible.
In the following, I will try to show that Stroud’s skeptical objection does not bury world-directed TAs once and for all; on the contrary, it even helps to leverage the possibility of a species of valid world-directed TAs.
My argument starts from the observation that Stroud’s skepticism is not a mere guideline for refuting world-directed TAs on a case-by-case basis, but that it makes the highly non-trivial claim that all possible world-directed TAs are invalid. The whole consensus that Stroud’s skepticism is the be-all and end-all of the debate relies on the sense that it gives us some a priori reason to suppose that any world-directed TA whatsoever will suffer from the same fundamental flaw. In Stroud’s skeptical argument this flaw is exploited by the so-called ‘substitution objection’: for any transcendental conditional ‘X is only possible if p’, the enabling condition p can always be substituted by the necessary belief that p. In other words: world-directed TAs only show us how we must think in order to account for some subjective capacity X being possible, but we cannot from this infer how things really are.
In Section 2 of this paper, I will go through the ways that the Stroudian skeptic could justify this substitution objection to license a perfectly general refutation of world-directed TAs. As it will turn out, the Stroudian must appeal to much more substantive claims than is usually supposed. Ultimately, as I will argue in Section 2.4.1, Stroud’s substitution objection rests on a certain realist conception of objectivity that cannot be boiled down to a set of logical, semantic, or modal intuitions. Rather, the claim that substitution holds generally and for a priori reasons requires a modest TA that shows this conception of objectivity to be indispensable for any ascription of beliefs about the world. I will argue this in 2.4.2 and show which modest TA the Stroudian must subscribe to unless they do not want to end up in a stalemate of competing modal intuitions with proponents of TAs.
Section 3 uses this result to ensnare the Stroudian skeptic in a dialectical dilemma: on the one hand, they need the moderate TA specified in Section 2.4 to uphold their skeptical challenge in its full generality, but, on the other hand, this TA brings with it the commitment to a distinction which restricts the scope of the skeptical challenge, namely to ‘empirical’ instead of ‘transcendental’ truths about the world. The work of Sections 3.1–2 is to show precisely how the Stroudian’s conception of objectivity leads to a kind of antinomy unless it includes a distinction between empirical and transcendental truths about the world. As a consequence, this distinction must also inform the Stroudian’s justification of their substitution objection, as I show in Section 3.3.
The result is, first, that Stroud’s substitution objection only holds water insofar as we cannot use world-directed TAs to derive empirical truths. Second, I show that the Stroudian’s acceptance of the moderate TA for their conception of objectivity means that they positively have to endorse the possibility of a species of world- or truth-directed transcendental arguments that derive transcendental truths about the world. Note that this is merely a result concerning Stroud’s meta-epistemological skepticism about the validity of TAs (I am not concerned with vindicating TAs as an antidote to external world skepticism).2
Section 4 discusses objections to my strategy of reinstating world-directed TAs via the above dialectical dilemma. I focus on ways the Stroudian skeptic could try to re-apply their substitution objection and to characterize transcendental beliefs in terms of their ‘invulnerability’ to doubt. Stern’s (2017) problem of merely ‘silencing’ the skeptic instead of refuting them is also discussed. My replies to these objections draw on Wittgenstein’s analogy of the meter-measure in Paris: transcendental beliefs constitute our very standard of objectivity, thus distinctions which presuppose this standard—for example, between ‘psychological’ or ‘non-psychological’ truths—do not apply to them.
In the rest of the present section, I will first (§1.1) give an exposition of Stroud’s skeptical objection to transcendental arguments which focuses on the bare-bones structure of both the argument type and the objection. I will then (§1.2) briefly sketch Stroud’s account of what transcendental arguments at their best can show us, namely the “invulnerability” of certain beliefs to revision or critique.
1.1. The Structure of Transcendental Arguments and Stroud’s Objection
As a working definition, I understand a transcendental argument to be an argument which meets the following criteria: (i) it is logically coherent; (ii) its conclusion is not an analytic truth; (iii) it establishes a conditional of the form ⌜X is only possible if p⌝, where ‘X’ is substitutable by ‘language’, ‘thought’, ‘experience’ or a more specific conceptual capacity (cf. Stern 2000: 10). If ‘p’ designates a proposition about a state of affairs in the world, the TA is of the “world-directed” kind (cf. Stern 2000: 10).
The basic idea behind this definition is that X is something that not even the most hard-headed skeptic could reasonably deny, whereas p is something the skeptic doubts to be true, which is not analytically contained in (tautologically implied by) the concept or obtaining of X. Given the transcendental conditional ‘X is only possible if p is true’, it is then demonstrated to the skeptic that the falsity of p is actually inconceivable. For example, Kant’s Refutation of Idealism can be construed as such an argument:3
(1) I am conscious of my existence as determined in time (= X).
(2) All time determination presupposes something permanent in perception.
(3) But this permanent something cannot be an intuition within me.
(4) Hence, determination of my existence in time is only possible through the existence of actual things that I perceive outside of me (= p).
Stroud’s dilemma is a skeptical challenge raised against world-directed TAs in general. Put briefly, the dilemma is the following: (d1) assuming some form of idealism to be true renders world-directed TAs superfluous; (d2) without assuming some form of idealism, world-directed TAs are unable to establish their key premise, that is, a transcendental conditional which necessarily links the possibility of thought to the truth of a non-psychological statement. Stroud’s dilemma is best formulated as a three-step dialectical argument. This dialectical structure needs to be made explicit because every strategy in defense of world-directed TAs is also vulnerable to it.
The first step of the dialectic, and on my reading the most crucial, is the ‘substitution objection’: (1) whenever a TA establishes the transcendental conditional ‘X is only possible if p is true’, the skeptic may claim that ‘p is true’ can be substituted by ‘p appears to be true’ or ‘p is believed to be true’ whilst preserving the truth of the antecedent. Hence, the possibility of X is already made sufficiently intelligible by the assumption that we believe p to be the case, leaving open the skeptical possibility that p is in fact not the case. Given the substitution-move, the most that a valid TA has shown is the necessity of a certain belief that p being held given that some X is possible. Regarding the above version of Kant’s Refutation, substitution would state that if determination of my existence in time is possible, then I must believe in the existence of actual things outside of myself.
Once the substitution objection has gone through, world-directed TAs stand in need of foreign aid. As their conclusions seem restricted to demonstrating the necessity of a belief, it still needs to be shown that this belief must also be true. This leads to step (2), the ‘bridging problem’: if there is no necessary connection between psychological facts like beliefs and non-psychological facts about the world, the truth of the belief in question cannot be derived. We require an additional “bridge of necessity” (Stroud 2000a: 159) that holds between having a certain belief that p and this belief actually being true.
If the bridging problem is accepted, the only remaining remedy is to claim either that there indeed is such a ‘bridge’ between believing and being true, or between psychological and non-psychological facts more generally—or that no bridge is needed, because there is after all no substantive distinction between the subjective and objective. Both claims, however, would amount to (3) assuming a form of idealism, which can be seen as inherently problematic or at least question-begging when facing the skeptic.
Stroud’s prime example for idealism is verificationism, that is, the claim that if we employ a concept, then we must have satisfiable criteria for applying it and know whether these criteria have been satisfied (Stroud 1968: 247). In that case, there is no special TA required to show that the truth of some proposition p is a condition of the possibility of some X, as the link to truth is established independently and generally by the assumption of idealism. Regarding Kant’s Refutation, we would not need to consider the specific relation between inner and outer experience, but could just rely on the idealist assumption that if outer experience is a meaningful concept, then we will know whether it applies.
As shown, what underlies Stroud’s dilemma is the following dialectical sequence or trilemma:
-
(I) Substitution-objection
(= restricting the TA’s conclusion to mere belief)
-
(II) Bridging Problem
(= diagnosing a gap between believing and being true)
-
(III) Idealism Problem
(= forcing the gap to be bridged by the extraneous assumption of idealism)
As the above setup of the argument makes apparent, the success of the substitution-objection is its watershed moment: it is only because of substitutability that transcendental conditionals seem restricted to mere belief and/or to require an extraneous bridging principle (i.e., an idealist underpinning). Hence, any robust defense of world-directed TAs must target the substitution-objection. This strategy will be pursued further in Section 2.
1.2. Invulnerability
Stroud’s substitution-objection is key both to his attempted debunking of ‘ambitious’, world-directed TAs as well as to his positive account of what anti-skeptical mileage we can coax out of ‘modest’ TAs. According to the substitution-objection, the most that any TA can show is that a certain belief is “invulnerable” to revision or critique. In this section, I will sketch Stroud’s notion of invulnerability, as it is fundamental to understanding his approach and because it will be needed as a point of contrast in the dilemma developed in Section 3.
Stroud’s notion of invulnerability is a variation on Moore’s paradox, which states that, if I believe that p, it is inconsistent for me to assert that not-p.4 This is exemplified by the contradiction involved in asserting ‘I believe that it is raining and it is not raining’. Of course, it is still possible that my belief is mistaken, that is, the conjuncts ‘I believe that it is raining’ and ‘It is not raining’ are not logically contradictory. But their conjunction cannot consistently be asserted or believed by anyone.
For Stroud, TAs are a way to show that a certain proposition has this special ‘Moorean’ status of not being something that we can consistently deny or recognize as false given the beliefs we have. This is because Stroud’s substitution objection still allows for a successful moderate TA to show that some belief that p is a necessary condition of thought. Hence, it would be necessary for anyone to have this belief if they think at all. Therefore, just like in Moore’s paradox, no one could consistently deny that p or judge that not-p. For if someone denied that p, their denial would be an act of thinking, which (by hypothesis) entails that they must believe p to be true; hence, their denial of p would be a Moore-paradoxical assertion. The supposed TA would have thus shown the belief that p to be invulnerable to revision or critique.
However, according to Stroud’s substitution-objection, a belief’s invulnerability does not entail its truth. In fact, Stroud thinks that invulnerability comes with a “metaphysical dissatisfaction”, because it precludes “our gaining the kind of distance we need for reaching a satisfying verdict one way or the other on the metaphysical status of those ways of thinking” (2011: 140). To show that a belief which is a necessary condition of thought could never be truly denied would require a successful world-directed TA. In Stroud’s terms, such a belief would be part of a privileged class of propositions, which are both invulnerable and true if there is any thought at all.
2. How (Not) to Justify Stroud’s Substitution Objection
In applying the substitution objection, Stroud makes the tacit assumption that it can be applied across the board without question, hence that its application is (i) completely general and (ii) certain to hold regardless of the specific content of a certain world-directed TA. When made explicit, this assumption serves to underscore that Stroud must give a substantive justification of the substitution-objection for it to be admissible.
Stroud’s objection has arguably become so influential precisely because it presents a general argument against world-directed TAs which is supposed to apply to them as a class. Stroud departs from the diagnosis that the transcendental conditions which world-directed TAs intend to uncover are propositions which belong to the privileged class: “each member of which must be true in order for there to be any language, and which consequently cannot be denied truly by anyone, and whose negations cannot be asserted truly by anyone” (1968: 253).5 Stroud’s substitution-move pertains to the “way of proving, of any particular member [of the privileged class], that it is a member” (1968: 254). It thus presents a perfectly general objection pertaining to every TA which tries to show that some proposition S is a member of the privileged class. For each candidate proposition S, Stroud proposes that
the skeptic can always very plausibly insist [my emphasis] that it is enough to make language possible if we believe that S is true, or if it looks for all the world as if it is, but that S needn’t actually be true. (1968: 255)
Currently of interest is Stroud’s contention that the above substitution can “always very plausibly” be made, which commits him to the (i) generality and (ii) certainty of its applicability. Given that a method for debunking world-directed TAs in general is sought, nothing less should do. If Stroud had only sketched a general strategy to guide case-by-case refutations of certain TAs, no general skepticism about TAs would be warranted and substitutability would be an open question for every new world-directed TA put forth.
Hence, the full skeptical force of Stroud’s trilemma has at least the following success conditions: first, the substitution-move must be applicable to any world-directed TA, irrespective of the particular concepts involved; second, this general applicability must be known to hold, which in effect means that it must be in some sense known a priori that world-directed TAs are susceptible to substitution.
What reasons does Stroud give that substitution applies across the board and can be known to thus apply? And which reasons could he give? In the following sub-sections, I will take stock of Stroud’s explicit statements on the justification of his substitution-objection and then go through the different options available to him. As it will turn out, the assumptions required to secure the substitution-objection are more substantive than they may appear at first glance in Stroud’s gloss. Thus, in each successive sub-section, a more substantive justification will be advanced and criticized, with only the final one—a modest transcendental argument for a conception of objectivity (§2.4)—being found to be fit for the purpose.6
2.1 Logic/Semantics
Stroud’s explicit glosses on how general substitution is justified primarily refer to logical and semantic considerations. Stroud’s most detailed account of substitution is found in his “Kantian Arguments, Conceptual Capacities, and Invulnerability” (2000a), it concerns the direct inference from believing or thinking that p to the truth of p. According to Stroud, if there is no such inference, then the conclusions of world-directed TAs are always substitutable with mere beliefs, because their premises just concern beliefs/thoughts as well:
What calls into question the validity of the last step of would-be transcendental arguments from the way we think to the way things are is the apparently simple logical observation that something’s being so does not follow from its being thought or believed to be so. (2000a: 165f.)
Since truth cannot follow deductively from belief, so Stroud’s argument seems to go, the possibility of a belief/thought cannot imply that some proposition must be true.
Stroud (1968) has the skeptic employ a similar distinction between warranted assertability and truth.7 This distinction can be considered to be constitutive of any judgement that a proposition is true, insofar as we must thereby distinguish the act of assertion from what is asserted. Whilst the capacity to make meaningful assertions certainly seems conditioned by (other speakers) being able to assert and believe things, this does not necessarily transfer to the truth or falsity of what is asserted. In this vein, the justification of substitution seems to run as follows: strong TAs concern the conditions under which meaningful thought or language is possible, but something can be meaningful simply in virtue of its warranted assertability, that is, without being true. Hence the warranted assertability of a transcendental condition can always be substituted for its being true.8
Stroud’s “simple logical observation” is not perfectly general however, as there are logically self-guaranteeing thoughts such as those expressed by “This utterance expresses an English sentence” or “I am thinking”. When these sentences are asserted, the act of asserting is part of their content. In these cases, merely thinking or believing something does logically warrant the inference to its truth.9 Since Stroud concedes such cases (2000a: 157), his justification must be modified.
The most minimal revision of Stroud’s “simple logical observation” would be to frame it as a semantic claim about the concepts thought and belief and their corresponding propositional attitudes. The transcendental inference from how we think to how things are would thus be blocked ‘from the inside’, making the following impossible:
We start with what we can call psychological premisses—statements whose main verb is a psychological verb like “think” or “believe”—and somehow reach non-psychological conclusions which say simply how things are, not that people think things are a certain way. (Stroud 2000c: 210)
Here, the distinction between belief and truth is sharpened and turned into a semantic distinction between ‘psychological’ and ‘non-psychological’ facts, that is, those which essentially involve the attitudes of subjects and those which do not. Stroud thereby avoids the objection from self-guaranteeing thoughts like “I am thinking”, because the relevant facts inferred by world-directed TAs are ‘non-psychological’, as opposed to ‘psychological’ facts like that I am thinking. To sum up, Stroud’s core idea seems to be expressed by the following question: “Can we ever really reach such conclusions from such beginnings?” (Stroud 2000c: 212). Apparently, humble beginnings preclude a proposition’s being recognized as belonging to the ‘privileged class’ according to Stroud.
However, this way of justifying substitution as a semantic point about belief begs the question against world-directed TAs. For it mischaracterizes how TAs link some conditioned X to its necessary condition p: the condition p is not supposed to be fulfilled simply because we believe it to be, but rather because of what p is: something without which X is not possible. Defenders of TAs can thus agree with Stroud’s semantic point: “Our being wrong, given that we believe something, is not in that sense an impossibility” (Stroud 2000a: 166, emphasis mine). Given just the fact that I believe something or other surely does not rule out being wrong about it. But TAs do not intend to infer non-psychological conclusions just from the fact that something is believed, but rather from the fact that a specific conditioned is possible. Hence, defenders of TAs can appeal to the uniqueness of transcendental conditionals against Stroud’s substitution-move (cf. Section 1): that given some conditioned, it is simply inconceivable that its non-psychological conditions are not fulfilled, because there is a unique modal link between these conditions and this conditioned.10 In other words, it is the truth of p and only the truth of p that is sufficient to serve as a condition of the possibility of X. Kant’s Refutation might be defended this way, given that it may seem inconceivable that a mere belief (or inner intuition) play the role of an outer substance. Cassam raises a similar point: “we might insist [. . .] that it is the existence of physical objects and not merely belief in their existence which constitutes a necessary condition of the possibility of experience, and if this is true, there will simply be no gap to be bridged” (1987: 356). Such a claim may seem equally contentious, but it is not ruled out by Stroud’s semantic point about belief.
To conclude this section, both Stroud’s logical point about holding to be true versus being true and his semantic point about being believed versus having non-psychological status have begged the question against world-directed TAs. Each correctly states that something is not true (or has non-psychological status) simply in virtue of being believed, but this does not rule out that belief and truth can be necessarily connected at all.
2.2. Modal Intuition
Stroud’s justification of the substitution-objection was seen to beg the question from the standpoint of truth-directed TAs, and in the following remarks, Stroud concedes this:
The most ambitious form of transcendental argument would wipe out the alleged challenge right at the beginning, by demonstrating of some of the things we believe that their truth is a necessary condition of our thinking and believing them. That would imply that the thought from which the putative challenge appears to begin is actually a contradiction; what it thinks is possible is not really a possibility after all. We simply could not have all those beliefs if they were in fact all false. (2000a: 166)
Here, Stroud is in effect describing the case of a proposition being part of the privileged class: its truth is constitutive of its being meaningful, in virtue of being a necessary condition of meaningful thought or language in general.11 Propositions of this class thereby raise the challenge of uniqueness against Stroud. Thus, if the modal link between a conditioned and the truth of its transcendental conditions is strong enough, substitution will not be possible, as no other ‘substitute conditions’ will do. This is precisely the case for members of the privileged class: even thinking about their falsehood is not possible (e.g., meaningful), unless they are actually true.
This adds a helpful criterion for deciding whether a proposition belongs to the privileged class, namely that what the skeptic “thinks is possible is not really a possibility after all” (Stroud 2000a: 166). Conversely, the justification of substitution amounts to showing that there always remains the skeptical possibility that a transcendental condition may turn out to be false. Stroud endorses precisely this view regarding our beliefs about transcendental conditions: “I think we must grant that there is such a possibility [. . .]. Given only that we believe them, it is still possible for them to be false” (2000a: 166).
As we have seen, the logical and semantic justification of this perpetual ‘skeptical possibility’ is insufficient. But the core issue has now become clear: whether a truth-directed TA can show that the skeptical possibility cannot arise regarding its conclusion. The bone of contention between proponents and skeptics of TAs thus seems to regard knowledge or intuitions about a modal fact. Proponents of TAs appeal to their modal knowledge that the truth of some transcendental condition p is necessarily connected to some conditioned X. Skeptics like Stroud, on the other hand, appeal to their modal intuition that it still seems possible for p to be false in spite of our necessarily believing in its truth. As this way of rendering the dialectic makes apparent, we are thus in a stalemate, as one modal intuition or knowledge claim seems just as good as the other, contrary one.
Thus, the skeptic has to endorse the validity of modal intuitions himself and hence has to grant the same to defenders of TAs.12 Ultimately, this dialectical strategy seems to end up returning to the stalemate of two equipollent but opposing modal intuitions.13 Stroud lays claim to modal intuitions which, considered on their own, seem just as contentious as the similarly general and a priori claims to necessity made by world-directed TAs. In particular, Stroud appeals to the substantive modal intuition that there will necessarily and a priori be a skeptical possibility for each purportedly transcendental condition of thought or experience. Therefore, the justification of the substitution objection requires Stroud’s modal claim to be further grounded in something else than mere modal intuition or apparent conceivability.
2.3. Realism
The most straightforward way for Stroud to lay claim to the required skeptical possibility seems to be an appeal to realism, such that it is, as Stern clarifies, “just a feature of the mind-independence of the world which makes it more opaque to us in this way, so that our modal claims concerning it are correspondingly more problematic, than they are concerning connections between our thinking” (2007: 147). Indeed, some of Stroud’s remarks take the previously employed semantic and modal justifications of substitution to be grounded in the world’s mind-independence:
[The Kantian enterprise of world-directed TAs] must explain how we can proceed deductively, or in some sense necessarily, from facts about how we think and experience things to conclusions which appear to say how things are independently of all human thought and experience. (2000a: 158, emphasis mine)
Substitution is thus always justified, because there just cannot be necessary connections between our thinking and the world, if the latter is to remain mind-independent. Hence it is simply a metaphysical truth that what we must assume or ascribe is always outrun by how things are.
However, is Stroud’s skeptic truly licensed to avail themselves of a realist justification in such a straightforward manner? Being a skeptic, they may not be able to endorse realism directly, but they can plausibly claim that realism is what we should want to endorse, if we want to steer clear of idealism. Hence, the skeptic could argue that proponents of world-directed TAs are either idealists (and are thus caught in third horn of Stroud’s trilemma) or they are realists and must succumb to substitution in the way sketched above.
It is clear that the skeptic’s appeal to realism as a metaphysical claim must serve to make an epistemic point: given the world’s mind-independence, we could not discover the necessary connections between thought and world relevant to world-directed TAs (and also required by what may back them up, like an idealist position). Stroud’s realist line of argument should therefore run as follows: there is no necessary connection of beliefs and worldly facts that is cognizable by us, because there is no metaphysical dependence of the world on thought that would warrant or imply such an inference from invulnerable beliefs to matters of fact. Since we cannot assume to have a priori knowledge about a mind-independent world, all we have to go on is necessary connections between ways of thinking, for example, regarding our conceptual capacities. But as the world is not dependent on us nor on our capacities, inconceivability-to-us is no useful guide for proving modal facts. Since realism thus disconnects conceivability from metaphysical possibility, there is no inference from the invulnerability of a belief to ruling out the skeptical possibility of its being false.
However, I think that even such an amended ‘epistemic’ appeal to realism turns out to be either circular or self-refuting. For it either (i) already presupposes that substitution is justified or (ii) itself amounts to a world-directed TA (or a form of verificationism). To see the former (i), consider what the point of departure was: the mind-independence of the world was to rule out that we may discover a priori necessary connections between thought and world. But for this it was already assumed that only a dependence-relation between mind and world could account for our knowledge of such a necessary connection. Alternatively, the plain inconceivability of falsehood that accrues to propositions of the ‘privileged class’, might warrant the same conclusion. Analogously, the sheer inconceivability of certain logical contradictions, for example, a round square or an even prime number n > 2, also seems sufficient for our knowledge-claim that these things do not really exist. On its own, therefore, the lack of a dependence-relation is not sufficient to rule out this kind of inconceivability. Rather, the epistemic appeal to realism needs to tacitly presuppose that necessarily thinking in some way is simply a psychological fact about our cognitive capacities. As our capacities may be limited, inconceivability-to-us can never establish a world-directed transcendental claim.14 But thus limiting the scope of inconceivability to necessary connections among beliefs (as opposed to connections between beliefs and matters of fact), is just another way of making Stroud’s substitution-move. Hence, to assume that the world’s mind-independence generally underwrites the relevant skeptical possibility already presupposes substitutability. In this vein, appeal to realism for justifying the substitution-move would be circular.
Is there another way realism could underwrite skepticism about world-directed TAs which does not presuppose that substitution is justified? Not without (ii) being self-refuting, as I will now argue, because the realist would have to rule out uniqueness in some other way. Without presupposing substitutability, uniqueness can only be ruled out given actual knowledge of certain modal facts about the world, for example, whether some proposition p could in fact have been false. In other words, the realist must in each considered case know that p is a proposition which holds irrespective of—that is, without any necessary connection to—our having (true or false) beliefs about it. This is not trivial, as there do seem to be certain necessary connections between psychological facts and other facts about the world. For instance, our mental states arguably supervene on our brain states and many other things, for example, languages or social institutions, also do not seem wholly independent from the existence of minds.15 In the case at hand, the required modal knowledge is not going to be empirical or could not receive adequate empirical justification, since it has to underwrite the complete generality of the substitution-objection. But if it is to be a priori, then the realist would have effectively produced a world-directed TA themselves. For they need to claim that they know a priori that the modal fact obtains that any candidate transcendental condition p could be false while its conditioned X is possible. In other words, there is a distinct mismatch between the position of metaphysical realism, which is supposed to restrict all a priori modal knowledge about the world, and its being used to make a first-order claim that apparently requires a priori modal knowledge about the world, namely the independence of certain kinds of facts from our beliefs and subjective capacities.
As it turns out then, a direct or indirect commitment to metaphysical realism is, on its own, not sufficient to justify the generality and certainty of the substitution-objection.
2.4. The Indispensability of Objectivity
I have tried to show that Stroud’s substitution objection requires a much more substantive and possibly contentious justification than is usually presumed. In addition, the cascaded structure of my argument acts as a heuristic for isolating precisely where the source for the plausibility and power of Stroud’s objection lies. In this section, I will use this heuristic to show, first (§2.4.1), that Stroud’s objection relies on a certain conception of objectivity which is supposed to inform our understanding of what transcendental arguments are trying to do. That is, the objection is anchored not in contentious metaphysical claims but rather in claims about our conceptual scheme which proponents of ambitious transcendental arguments presuppose, that is, when describing what it is to draw conclusions about objective matters of fact from what is needed for any experience to be possible. This best serves to explain the wide acknowledgement of Stroud’s objection and the strong intuition of its general applicability, for it does not require subscribing to a metaphysical doctrine but only appeals to a shared understanding of what it means to say that our beliefs and knowledge claims are about something that is objectively the case.
In a second step (§2.4.2), I will show that the Stroudian skeptic must rely on a modest transcendental argument in order to justify the generality and certainty of the substitution objection. That is, the Stroudian needs to endorse the transcendental claim that their realist conception of objectivity is essentially bound up with our conceptual capacity to ascribe knowledge and beliefs about the world. This claim requires a modest transcendental argument. Only if we are thus necessarily committed to the requisite realist conception of objectivity will we have to concede that the substitution objection based on this conception holds generally and a priori, because endorsing it will be seen to be a necessary condition for ascribing beliefs about the world such as those which figure in world-directed transcendental arguments.
2.4.1. Stroud’s Conception of Objectivity as the Flipside of His Skepticism
Stroud’s substitution objection, crudely put, says that premises about ‘subjective’ facts of experience or thought do not license an inference to what is ‘objectively’ the case. My negative argument in Sections 2.1–3 probed for the ways in which this basic idea could be made more precise and given a rigorous justification. As Sections 2.1–2 showed, certain logical, semantic, and modal intuitions are integral to Stroud’s objection but they are insufficient on their own. Section 2.3 further showed that, although the substitution objection operates with a commitment to realism, it is also not sufficient to appeal to first-order metaphysical claims that the world is in fact thus and so. Stroud’s trademark contrast between what holds ‘subjectively’ and what is ‘objectively’ the case must therefore be based on different grounds. These grounds are not first-order claims about the world and not per se claims about our language-use or our intuitions. Rather, it seems that Stroud actually relies on second-order claims which state how we must think about the world if we say that we have true beliefs or knowledge about the world or that certain things are objectively the case.
That such a conception of objectivity is what actually underlies Stroud’s substitution objection can be seen from his critique of Davidson in his essay “Radical Interpretation and Philosophical Scepticism” (2000b). In this essay, Stroud criticizes Davidson’s transcendental argument that adhering to the ‘principle of charity’ when interpreting the utterances of speakers is not optional, but a necessary condition of interpreting them at all.16 Hence, I can only find the utterances of a speaker to be meaningful when I take them to express largely true beliefs. This amounts to a kind of world-directed TA, which issues into the conclusion that “belief is in its nature veridical” (2000b: 196).
In his discussion of Davidson’s conclusion, Stroud entertains the question whether it might have the status of a proposition belonging to the ‘privileged class’, in which case the radical or overwhelming falsehood of a speaker’s belief-set would be entirely inconceivable.17 Against this reading, Stroud employs his substitution objection to claim that it is sufficient to render interpretation possible if we must always find those we interpret to have true beliefs, that is, “that belief-attribution is in its nature largely truth-ascribing” (2000b: 197, emphasis mine). This ascription of true belief is, of course, to be distinguished from the ascribed beliefs actually being true.
It is interesting to observe how Stroud justifies his substitution objection in this case. As we should expect, he refers to the skeptical possibility that things could in fact be otherwise, but Stroud then goes on to connect it to the claim to objectivity that is implicit in any claim to veridical belief:
I think we must grant the abstract possibility of a set of beliefs’ being all or mostly false in the minimal sense that the truth of all or most or even any of them does not follow simply from their being held. To insist otherwise seems to me to threaten the objectivity of what we believe to be so. It would be to deny that, considered all together, the truth or falsity of the things we believe is independent of their being believed to be so. (2000b: 197, emphasis mine)
In the above passage, substitution is justified as following from an inherent commitment to objectivity which we must undertake when ascribing belief. Hence, as Stroud suggests here, if I could not imagine you being completely wrong about something or even everything, then I also could not ascribe beliefs to you which are about something truly objective. For only that which is independent from subjectively held beliefs seems to count as objective in the full sense. But if you claim to have beliefs about something objective, which is thus independent of your having beliefs, then you must also take the skeptical possibility to be conceivable that you may be completely wrong about it.
In his book The Significance of Philosophical Scepticism (1984), Stroud confirms the diagnosis that it is the general claim to objectivity which underlies his skepticism:
What we aspire to and eventually claim to know is something that holds quite independently of our knowing it or of our being in a position reasonably to assert it. That is the very idea of objectivity. (1984: 78)
Since knowing something objective is our own aspiration and claim, we must also concede the relevant skeptical possibility of being wrong about beliefs we must nonetheless hold to be true. For Stroud, the desire for such a detached perspective of ourselves is at the very root both of our conception of an objective world and of skepticism.18
2.4.2. The Need for a Modest Transcendental Argument
Understanding Stroud’s skepticism to be based on a conception of objectivity is still not sufficient to justify why we must agree with Stroud that the substitution objection applies to all world-directed TAs in general and that this is in some sense evident a priori from the ambitiousness of what these TAs are trying to achieve. To see this, we need to be shown, first, that Stroud’s realist conception of objectivity is non-optional, that is, that there cannot be alternative, perhaps anti-realist conceptions of objectivity on equal footing with Stroud’s. Such an alternative would lead back into a stalemate of competing intuitions or conceptual schemes (cf. Section 2.2). Second, we need to be shown how exactly employing such a realist conception of objectivity is tantamount to accepting Stroud’s substitution objection in its full generality.
These desiderata can only be met by a moderate transcendental argument, for otherwise it could not be shown that proponents of TAs must also endorse Stroud’s conception of objectivity and that the substitution objection based on it is thus indeed perfectly general and a priori. The Stroudian skeptic will not be able to break the stalemate of competing intuitions without the help of transcendental claims about the necessity of their conception of objectivity—that was developed in Sections 2.1–3. And indeed, as was indicated in the previous sub-section, Stroud himself gestures at such a transcendental justification by tying his conception of objectivity to the very ascription of knowledge and belief.
Given that it is the essential common ground the skeptic shares with proponents of TAs, there seems to be no other good starting point for the required TA than the capacity of ascribing beliefs about the world:
(1) We ascribe beliefs about the world (to others or to ourselves).
(2) Ascribing beliefs about the world is possible only if we think of the world as containing objective facts that ground the truth of beliefs about these facts.
(2) is a transcendental claim because it does not merely state what we in fact understand by the concept of world-directed belief, rather, it states what we must presuppose when applying this concept to persons. In ascribing beliefs about the world, we must operate with a certain understanding of what enables these beliefs’ being open to an objective assessment. In a first step, this enabling condition is the objective fact which functions as a truth-maker. This enabling condition can be specified further regarding the presuppositions we must make with respect to the objectivity or mind-independence of these objective facts:
(3) Thinking of the world as containing objective facts is possible only if we take these facts to obtain independently of anyone’s believing that they obtain.
(4) Taking objective facts to obtain independently of anyone’s believing that they obtain is possible only if it is conceivable that any or all of our beliefs about objective facts could be false.
The conception of objectivity that emerges from (2)–(4) is realist in a broad sense: it does not confine objective facts to narrowly mind-independent entities like, for example, solar systems, but rather is supposed to reflect what Adrian Moore has called “the Basic Assumption” that “representations are representations of what is there anyway” (1997: 74). In Burge’s sense it is a “subject-matter vertical conception” of objectivity (2010: 51),19 because it is ultimately a view on the subject-matter of world-directed beliefs, namely that this subject-matter is existentially independent of being truly represented by anyone. However, the Stroudian skeptic is not committed to a specific way of unpacking this conception beyond (2)–(4).20 Finally note that the above is a sketch for the kind of transcendental argument the Stroudian skeptic will need to appeal to—it is not itself the argument for this realist conception of objectivity.21 My claim is meta-theoretical: in order to justify their substitution objection, the Stroudian skeptic will need to endorse such a (moderate) transcendental argument.
Unless global error about the world is conceivable, the Stroudian skeptic has no means of generally casting into doubt any transcendental claim that some X is only possible given some non-psychological fact p about the world. As I detail below, the conceivability of global error puts any transcendental conditional’s claim to modal uniqueness into question. With (4) we have linked the skeptical possibility decisive to bring down would-be ambitious TAs to the very capacity to ascribe beliefs about the world. This is a significant advance over the failed attempt in Section 2.2, to appeal to a self-standing modal intuition of this possibility which was seen to beg the question against proponents of TAs. From (4) we can derive the core intuition underlying the logical attempt at justification in Section 2.1:
(5) There is no deductively valid inference from the necessity of holding a belief about the world to its truth.
Moreover, we can derive from (4) and (5) the core intuition underlying the justification appealing to metaphysical realism in Section 2.3:
(6) Given only certain beliefs about the world, there is no way to know their truth a priori, for this would require either (a) their falsity being inconceivable or (b) their truth somehow being deductively inferred from the fact that we hold these beliefs.
Stroud’s substitution objection follows from the transcendental claims in (1)–(4) and the above derivations when we consider that it targets the purported ‘uniqueness’ of the enabling condition:
(7) [Uniqueness property:] An instance of the schema ⌜X is only possible if p is true⌝ has uniqueness iff it is inconceivable that X is possible when p is false.
Given (4) and (5), no transcendental conditional has uniqueness when it takes an objective fact about the world as a condition of the possibility of some psychological fact. Hence, because world-directed conditionals lack uniqueness and, given (6), because we lack an a priori method of deciding the truth of transcendental conditionals, substitutability follows:
(8) [Substitution objection:] It is undecidable a priori whether an instance of the schema ⌜X is only possible if p is true⌝ is true or whether ‘p is true’ can be substituted by ‘it is believed that p’, when ‘p’ refers to (a proposition about) an objective fact.
Since the substitution objection is derived in (2)–(7) from transcendental conditions of ascribing beliefs about the world and given that (1) we indeed ascribe world-directed beliefs, the required generality and a priori knowability of the substitution objection follows:
(9) We have an a priori reason to presume that the substitution objection in (8) applies to all world-directed transcendental arguments.
With this result, the Stroudian skeptic can effectively respond to the challenges raised by Brueckner (1983; 2010), Grundmann and Misselhorn (2003), and Stern (2007): there is no stalemate of intuitions, rather the conception of objectivity which underlies our shared conceptual scheme justifies the substitution objection against competing modal intuitions.
3. A Dialectical Dilemma for the Stroudian Skeptic
In the following, I will show that the Stroudian skeptic ends up in a dilemma: on the one hand, they need the above moderate TA to uphold the skeptical challenge of the substitution objection in its full generality, but, on the other hand, this TA brings with it the commitment to a distinction which restricts the scope of the skeptical challenge, namely to ‘empirical’ instead of ‘transcendental’ truths about the world.
The first part of the dilemma was developed above in Section 2: Stroud’s substitution-objection requires a specific kind of TA which contains the transcendental claims (1)–(4) about the conception of objectivity presupposed in belief-ascription about the world. In the following, I will develop the second part of the dilemma by reflecting on the fundamental status of this conception of objectivity. In Section 3.1, I will show that the Stroudian’s conception of objectivity leads into the following contradiction: it asks us to conceive of the skeptical possibility that all our beliefs about the world could be false while at the same time making us hold on to certain core realist beliefs that are bound up with our conception of objectivity. In Section 3.2, I show that this dialectical situation forces the skeptic’s hand: they need to endorse a disjunctive concept of world-directed belief in order to avoid such a self-refuting contradiction. In Section 3.3, I will show how this dialectical result helps reinstate world-directed TAs.
3.1. Deriving the Dilemma: Objectivity Taken Too Far
From the above TA in (1)–(4) it follows that believing the world to be a realm of objective facts is indispensable to our conception of objectivity:
(10) In ascribing beliefs about the world, we necessarily believe that the world contains objective facts that are independent of our having those beliefs and which ground the truth or falsity of our beliefs about them.
From its indispensability it also follows that (10) is an ‘invulnerable’ belief in Stroud’s terminology, that is, this belief cannot consistently be given up if we ascribe any beliefs about the world to anyone (see Section 1.2 for a discussion of Stroud’s notion of invulnerability). Now, in the above justification of the substitution objection, this core realist belief entails that we can conceive of the skeptical scenario that all our beliefs about the world are false. But this scenario should also include our core realist belief about the world expressed in (10). For our conception of objectivity implies the skeptical possibility of global error which in turn implies that the world might not be the way that our conception of objectivity says we must think it to be. In other words, qua being objective, the world is supposed to outrun the very concept of objectivity.22
As I will show now, this sort of self-application of our conception of objectivity is, in effect, objectivity taken too far. It leads to a contradiction rooted in our very conception of objectivity, which I think licenses the label of an ‘antinomy’. Later in Section 4, I will have more to say on how to characterize this antinomy properly, namely as treating the very standard of objectivity as something of which we can intelligibly ask whether it is objectively true or not.
So let us see where going through with conceiving of the scenario of global error—which is mandated by the conception of objective facts we must subscribe to according to (4)—really leaves the Stroudian skeptic:
(11) We must be able to conceive of the possibility that the world which our beliefs are about exists and that all of our beliefs about what the world is like are false.
(12) Hence, we can conceive of the possibility that (10) is false, that is, that our belief that the world contains objective facts which are independent of our beliefs about them is false.
Note that both (11) and (12) are claims about conceivability, which concern how we must make the skeptical scenario intelligible to us, for example, as a way the world could be. They are not claims about what we believe (or can believe) to be the case in the actual world. Nonetheless, (12) forces the Stroudian to consider what would be the case if the core realist belief expressed in (10) were false.
There are multiple ways to interpret the wide-scope negation of (10): (i) reject the existence of objective facts altogether, (ii) reject their role as truth-makers of our beliefs, or (iii) reject their independence from our beliefs. The first two interpretations contradict the supposition made in (11) that our beliefs are about the world albeit possibly being false. For rejecting the existence of objective facts as in (i) means giving up on the distinction between seeming so and being so that is needed to make sense of the very notion of world-directed belief.23 Similarly, rejecting objective facts as truth-makers as in (ii) would lead to the bizarre scenario in which we assume that there is a world containing objective facts but that these play no role in determining the truth or falsity of our beliefs. In this scenario, there is no intelligible connection between a belief’s truly or falsely representing the world and the way the world is objectively. Hence, (i) and (ii) must be rejected:
(13) If the world contained no objective facts, then—contrary to what was supposed in (11)—we could not think of it as a world that our beliefs are about.
(14) If the world contained objective facts which do not ground the truth or falsity of our beliefs about them, then—contrary to what was supposed in (11)—we could not think of it as a world that our beliefs are about.
To avoid contradicting the supposition, we are thus left with (iii) as an interpretation of the negation of (10):
(15) Given (12), we must think of the world as containing objective facts which are existentially dependent on our beliefs about them and which ground the truth of our beliefs about these facts.
Negating our core realist belief in this way forces us to conceive of a scenario where the world in effect satisfies an idealist conception of objectivity, because we must conceive of objective facts as dependent on us as believers. As we are holding on to the supposition that there is a world which we have beliefs about, this is the only way that we can understand the world being different from what the realist conception mandates that we believe.
But conceiving of such an existential dependence of facts on beliefs in (15) ensures that, in the skeptical scenario, there exists a truth-maker for at least some of our beliefs as long as we have beliefs.24 Hence, paradoxically, some of our beliefs must be true. Given the premises—that is, the existential dependence of facts on beliefs conceived of in (15), that these facts act as truth-makers for our beliefs, and that there in fact is a world which our beliefs are about—it follows that some of our beliefs must be made true by these facts. Thus, the scenario of global error that we initially tried to conceive of in (11) falls apart:
(16) Given (15) and that there is a world our beliefs are about, at least some of those beliefs must be conceived of as true—contrary to what was supposed in (11).
The first point to note is that this does not show the skeptical scenario of (11) to be inconceivable on its own, but only together with the assumption (12) that we must be able to conceive of our core realist belief about objectivity as being false. The latter implies that we must in effect accept some form of idealism as true in such a possible world. From this we derived (16), that is, that some of our beliefs about the world have to be true given this idealism. Only then does it follow that we cannot coherently conceive of the skeptical scenario of global error. The second point to note is that this result shows a genuine inconceivability and does not merely reflect the invulnerability of our core realist belief or our inability to consistently believe that the skeptical hypothesis is true. For this core realist belief (10) can indeed be coherently conceived of as false, namely in (15). The problem lies in the incompatibility of this assumption with the scenario of global error it was to be part of.
This result leads to the following contradiction: the Stroudian must be able to conceive of the skeptical possibility of global error, as it is essential for their conception of objectivity, but also cannot do so while using this conception. Since the Stroudian must regard their conception of objectivity as non-optional (by being committed to the TA rendered in Section 2.4), they must endorse the following antinomy:
(17) On the realist conception of objectivity, we must both think it possible that all of our beliefs about the world are false and cannot think this to be possible.
To recapitulate: our core realist belief about the world in (10) mandates that we should be able to conceive of the world as even independent of this very belief. In (15) this has led to the counterintuitive result that we must be able to hypothetically accept this core realist belief as false and thus to conceive of objective facts in general to be dependent on our having beliefs about them. In the following section, I will diagnose why (17) warrants the term ‘antinomy’, what distinguishes it from a Moorean form of paradox, and how it serves to complete the dialectical dilemma for the Stroudian skeptic.
3.2. Completing the Dilemma: Diagnosis of an Antinomy
The previous section tried to show that the Stroudian must endorse a contradiction in (17). This result resembles an antinomy in the Kantian sense, as it is a seemingly inescapable commitment to an untenable position. For Kant, antinomies are a cue that something has gone awry conceptually. In what follows, I draw on this analogy with the Kantian understanding of antinomies to clarify the kind of dialectical pressure that the argument for (17) puts on the Stroudian. (I am not thereby committed to any further exegetical claims about Kant nor do I presuppose Kant’s method in the dialectic.)
More specifically, the dialectical result arrived at in (17) resembles an antinomy in the Kantian sense, because, according to the Stroudian, we must necessarily endorse two contradicting claims. On the one hand, the TA in (1)–(4) has shown our conception of objectivity to be non-optional and to posit as a limit case the skeptical possibility that all our beliefs about the world are false. On the other hand, as an anti-thesis to this, the above argument in (10)–(16) has shown that we cannot consistently conceive of this skeptical scenario when endorsing the Stroudian’s conception of objectivity.
The antinomy might seem similar to a Moore-paradoxical thought (for a definition, see Section 1.2), though closer inspection shows that this is not so. (17) does not state that we necessarily hold some belief on pain of self-contradiction; it shows neither the invulnerability of believing that the skeptical hypothesis is possible nor the invulnerability of believing that some of our beliefs about the world are true. Rather, (17) shows that we must believe a contradiction if we endorse the modest TA for the Stroudian conception of objectivity. On its own, this is a merely negative result which threatens both Stroud’s skepticism as well as our conception of objectivity with unintelligibility.
In Kant, antinomies are symptomatic of a kind of category mistake, for example, treating ideas of reason as if they were concepts of experience, although ideas are concepts which are inherently inapplicable in experience. In the same vein, I think that (17) should alert us to a category mistake in how we have been applying our conception of objectivity. Analogous to Kantian ideas and concepts of experience, we have treated the core realist belief (10) that we are committed to on this conception as on a par with our other beliefs about the world. That is, we have treated our very standard for objectivity as something of which we can intelligibly ask whether it is objectively true or not (I will develop this diagnosis further in the conclusion Section 4).
As I will now try to show, the Stroudian is under pressure to revise their concept of a world-directed belief in order to resolve this antinomy. Kant rightly saw the kind of dialectical pressure such an antinomy exerts on those caught within it. Given that we seemingly must affirm two contradictory propositions, these must themselves contain a contradictory concept. Kant paradigmatically shows how, once the concept at the root of the antinomy has been revoked or revised, we can rightfully declare the propositions at issue as either both false or both (in differing senses) true (cf. Kant 1997: 93). Since both conjuncts in (17) have been in different ways necessitated by our conception of objectivity, they are non-optional for us. So we will have to opt for the latter way of resolving the dilemma that preserves both as true.
In the present case, the antinomy arises from the transcendental conditions of ascribing beliefs about the world, hence it is the notion of a belief’s being ‘world-directed’ that must be the root cause of the antinomy:
(18) Our concept of world-directed belief (or the concept of a capacity for having beliefs about the world) is covertly contradictory.
(19) Either the concepts of belief and world-directedness are contradictory, which seems implausible, or the concept of world-directed belief is ambiguous.
If there are different senses of ‘world-directed belief’, as reasoned in (19), then the contradiction could be resolved and, given suitable disambiguation, the truth of the two involved propositions preserved. I propose that the Stroudian skeptic is under pressure to do this in the following way:
(20) We must understand world-directed belief disjunctively in an ‘empirical’ sense and in a ‘transcendental’ sense in order to resolve the contradiction in (17).
Let’s first see how this resolves the apparent antinomy in (17):
(17*) Given the realist conception of objectivity, we must both think it possible that all of our empirical beliefs about the world are false and cannot think it possible that our transcendental beliefs about the world are false.
What forces the Stroudian skeptic to resolve the contradiction in (17) in precisely this way? Again, I think this follows from the structure of the dialectic Stroudians find themselves in. The dilemma arises because we employ a conception of objectivity that commits us to seemingly conflicting claims about the necessity and contingency of the world as a realm of objective facts. Hence, the dilemma prompts us to examine at which stage of the dialectic and in which context these claims are introduced.
Differentiating context will thus show us how we must disambiguate (17). The claim of contingency belongs to (4) and consists in a first-order description of objective facts which our conception commits us to, that is, as facts that are independent of our having beliefs about them. The claim of necessity belongs to (10) which gives a second-order description of how we are committed to this contingency claim, that is, that we must necessarily believe it when ascribing world-directed beliefs. However, both claims are about the world and thus do not seem to simply belong to different semantic levels. This co-referentiality was key for the above reductio-style dialectic in Section 3.1. To avoid contradiction, we thus need to regard these claims as expressing different senses in which we can refer to the world.
The above observations regarding context help specify these senses as follows. We refer to the world in an empirical sense when we make first-order claims about objective facts that pertain to features not necessarily presupposed by our conception of objectivity. We refer to the world in a transcendental sense when we make claims about the world which state necessary conditions of employing our conception of objectivity.
Hence, in their respective context, we need to disambiguate the above claims as follows:
(4*) Taking objective facts to obtain independently of anyone’s believing that they obtain is possible only if it is conceivable that any or all of our empirical beliefs about them could be false.
(10*) In ascribing beliefs about the world, we necessarily have the transcendental belief that the world contains objective facts that are independent of our having those beliefs and which ground the truth or falsity of our beliefs about them.
As was already laid out above, thus disambiguating the concept world-directed belief avoids the contradiction of (17) and yields the benign revised version (17*). Moreover, I have argued that the structure of the dialectic leading to (17) puts pressure on the Stroudian skeptic to resolve the contradiction in precisely this way.
This completes the set-up of the dialectical dilemma: As was shown in Section 2.4.2, the Stroudian must make use of a moderate TA to bolster their realist conception of objectivity in order to uphold the full generality and force of the substitution objection. The present and previous sections have shown that appealing to this TA ensnares the Stroudian in a contradiction unless they distinguish between transcendental and empirical beliefs about the world.
In the next section, I will turn to the payoff of this dilemma by showing that this distinction, which is forced upon the Stroudian skeptic, also forces them to concede that some world-directed TAs may be valid.
3.3. How the Dialectical Dilemma Reinstates World-Directed TAs
This last step of my argument shows how the above dialectical dilemma opens up a niche for world-directed TAs by showing that they are exempt from Stroud’s substitution objection in cases when they establish the truth of transcendental beliefs about the world. That transcendental beliefs are exempt in this way essentially follows from the disambiguation of the transcendental claim (4*) that the previous section argued for by way of a dialectical dilemma for Stroudians. This claim is at the center of Stroud’s justification of the substitution-objection which will now, given the dilemma laid out in Sections 3.1–2, have to be revised as follows:
(1) We ascribe beliefs about the world (to others or to ourselves).
(2) Ascribing beliefs about the world is possible only if we think of the world as containing objective facts that ground the truth of beliefs about these facts.
(3) Thinking of the world as containing objective facts is possible only if we take these facts to obtain independently of anyone’s believing that they obtain.
(4*) Taking objective facts to obtain independently of anyone’s believing that they obtain is possible only if it is conceivable that any or all of our empirical beliefs about them could be false.
Given the revision (4*), we also have to disambiguate all the steps in the argument which derive from it:
(5*) There is no deductively valid inference from the necessity of holding an empirical belief about the world to its truth.
(6*) Given only certain empirical beliefs about the world, there is no way to know their truth a priori.
(7) [Uniqueness property:] An instance of the schema ⌜X is only possible if p is true⌝ has uniqueness iff it is inconceivable that X is possible when p is false.
The universal applicability substitution objection cannot be derived from the revised premises (4*)–(6*), because they do not suffice to rule out that some transcendental conditionals could have uniqueness as defined in (7). All that can be derived is that uniqueness does not hold for transcendental claims involving empirical beliefs about the world (or propositions about objective facts which are representable by empirical beliefs). But nothing has been said about the species of transcendental beliefs and the objective facts about the world which correspond to them. Thus, the revised set of premises only justifies a restricted version of the substitution objection:
(8*) [Restricted substitution:] It is undecidable a priori whether an instance of the schema ⌜X is only possible if p is true⌝ is true or whether ‘p is true’ can be substituted by ‘it is believed that p’, when ‘p’ refers to the content of an empirical belief.
But where does this leave claims about enabling conditions that involve transcendental beliefs? With a view to reinstating world-directed TAs, the restriction of the substitution objection may not on its own break the stalemate of modal intuitions between the skeptic and proponents of TAs.
However, the dialectical dilemma in Section 3.1–2 has shown that, for the Stroudian, there must be at least one true transcendental belief, namely (10) as the core belief presupposed by the skeptic’s realist conception of objectivity. This shoulders the burden of showing that the class of transcendental beliefs is not empty (and thus that the move from the weaker (8*) to the stronger (8) is neither trivial nor warranted). Further, note that the transcendental belief (10) is derived from a moderate TA which the Stroudian must endorse if they want to retain their hold of the strong version of the substitution objection in (8). Therefore, we have an a priori reason to think that the original, strong version of the substitution objection does not hold generally and with a priori certainty:
(9*) We do not have an a priori reason to presume that the substitution objection in (8) applies to all world-directed transcendental arguments, but rather an a priori reason to think that it doesn’t.
This finally breaks the stalemate of modal intuitions which previous attempts at weakening Stroud’s substitution objection have faced (see Section 2.2). We have reached a point where the Stroudian skeptic is forced to grant that valid world-directed transcendental arguments of a certain kind are possible, namely those which prove transcendental beliefs about the world. This approach also preserves the contrary intuition which fueled the plausibility of Stroud’s substitution objection, namely that something is odd about trying to prove a conclusion about how things are from premises about how we must think. When we are talking about empirical beliefs which pertain to contingent matters of fact, this naturally seems odd. In the final section, I will try to elucidate the notion of a transcendental belief and show why the same sense of oddity would be misplaced in their case.
4. Objections: Invulnerability, Silencing, or Walking the Line?
My attempt at rendering world-directed TAs possible depends on a transformed understanding of what world-directed TAs are and do. Instead of crossing an at best questionable ‘bridge of necessity’ from psychological premises to non-psychological conclusions, they must be seen to remain on a level distinctly their own. This is the level of transcendental beliefs which cannot be categorized as being about either psychological or non-psychological propositions. Kant gives an apt analogy for the distinct status of transcendental propositions: they belong neither within the limits of empirical knowledge nor beyond them in a metaphysical realm, rather, they walk on the limiting line between these two realms (Kant 1997: 108). It is crucial that transcendental beliefs have such a neutral status relative to the distinctions with which the Stroudian skeptic demarcates modest and ambitious TAs. The second horn of the dialectical dilemma tried to show this, but there are a number of skeptical counter-objections that can be raised here.
I will try to address these objections now. The first objection tries to locate transcendental beliefs within the limits of merely psychological propositions by revealing them to be just a thinly veiled instance of Stroudian invulnerability. In response, I will argue that this rests on a misunderstanding by drawing on Wittgenstein’s famous analogy of the meter-measure in Paris:
There is one thing of which one can say neither that it is one metre long, nor that it is not one metre long, and that is the standard metre in Paris.—But this is [. . .] only to mark its peculiar role in the language-game of measuring with a metre-rule. (1968: §50)
The second objection attacks this Wittgensteinian move for merely ‘silencing’ the skeptic and not refuting them. I respond with the Kantian idea of ‘walking the line’ between an empirical and a meaningless, ‘transcendent’ concept use.
How could the Stroudian skeptic resist this result of the dialectical dilemma’s second horn? They will surely try to call out the notion of a ‘transcendental belief’ as being a merely repackaged version of invulnerability. To this end, the Stroudian could apply the substitution objection to the argument in Section 3.1: the antinomy of (17)—put briefly, that we both must and cannot think that all our beliefs could be false—accordingly would amount to nothing more than an instance of Moore’s paradox that shows our core realist belief (10) is invulnerable to critique. In that case, we might have furthered our understanding of the conceptual terrain regarding objectivity, but we would not have made headway on world-directed TAs.
This objection mischaracterizes what the argument in Section 3.1 has shown. That the core realist belief (10) is invulnerable is something that the moderate TA for the Stroudian’s conception of objectivity will have already shown. Rather, the antinomy in (17) shows that it is impossible to both reject the Stroudian realist conception of objectivity and hold on to the skeptical scenario of global error (and vice versa). This result is distinctly stronger than an invulnerability claim: we cannot make sense of the skeptical scenario without some (minimal) notion of the world’s independence from us. Without objectivity, there could not be fallibility. The attempt to conceive of a possible world where the skeptical scenario obtains here leads to a logical contradiction, because it also negates the core realist belief that is presupposed in stating how objective facts render our beliefs false. By contrast, framing this as a mere invulnerability claim would still allow that, in some possible world, all our beliefs could be false—we would merely add that we could never consistently see ourselves as inhabiting such a world.25
Again, the recalcitrant skeptic could try to restate the necessity of this resolution in terms of the substitution objection: it is only a fact about us and our limited imagination that the falsity of our transcendental beliefs about the world is inconceivable to us.26 Put in Stroud’s terms, this objection raises a ‘metaphysical dissatisfaction’ with our conception of objectivity: we are too thoroughly engaged in this conception to properly distance ourselves from it and assess its objective validity.
I think that formulating the objection in this way already makes apparent its absurdity: it does not make sense to disengage from the very conception on which the very distinction between our engaged perspective and an objective, disengaged standpoint is founded. This absurdity is of a kind with Wittgenstein’s remark that it does not make sense to ask whether the meter-measure kept in Paris is 1m long. In both cases, there is a presupposition for applying a criterion to which the criterion itself is not applicable.
Interestingly, Stroud himself discusses such a rejoinder to his substitution objection due to Davidson, who echoes Wittgenstein’s remark:
[‘]Communication [. . .] is the basis of our concept of objectivity, our recognition of a distinction between false and true belief. There is no going outside this standard to check whether we have things right, any more than we can check whether the platinum-iridium standard kept at the International Bureau of Weights and Standards in Sevres, France, weighs a kilogram. […][’]
If ‘there is no going outside this standard to check whether we have things right’, there is presumably no ‘going outside’ it even to assert that we have got things right, that our beliefs are for the most part true. (Stroud 2000b: 201, quoting from Davidson 2001b: 217f.)
The quote from Davidson refers to his principle of charity (discussed in Section 2.4.1) as forming the very standard of objectivity that cannot meaningfully be ‘checked’ or questioned regarding its objective validity. Stroud replies that this also precludes asserting the standard’s objective validity. It cannot be denied, but it also cannot be affirmed. This corresponds to the predicament of metaphysical dissatisfaction: precisely because the conception is invulnerable to a negative verdict, it is also barred from a positive verdict. But, according to Stroud, a successful world-directed TA would require being able to assert a positive verdict (see 2000b: 202).
I think that Stroud’s rejoinder contains an important insight but that he skews it by focusing too narrowly on Davidson’s specific claim that belief is in its nature veridical. For this claim purports to be about a presupposition for distinguishing between true and false beliefs, which renders stating the claim’s truth problematic in the way Stroud rightly points out. By contrast, the concept of transcendental belief developed in Section 3.2 still allows us to meaningfully assert these beliefs as true. Because transcendental beliefs are about how the world must be for the standard of objectivity to even be applicable to it, they cannot fail to be true of it. However, Stroud’s point does hold for those distinctions which directly presuppose the conception of objectivity, for example, those between ‘psychological’ and ‘non-psychological’ propositions (see Section 2.1) or between what is ‘subjectively’ or ‘objectively’ the case. On the one hand, this has the salvific effect that transcendental beliefs are invulnerable to Stroud’s further skeptical objections laid out in Section 1.1. We cannot raise the bridging problem (how to move from psychological premises to non-psychological conclusions), nor do transcendental beliefs license a form of idealism. On the other hand, this does lead to the dissatisfaction that the status of transcendental beliefs can only be articulated in the negative: they neither express ‘subjective’ truths about our ways of thinking nor ‘objective’ truths about empirical facts.
Does this mean that world-directed TAs which establish the truth of these transcendental beliefs work by silencing the meta-epistemological skeptic? The problem of ‘silencing’ is raised by Stern (2017). It raises a dialectical problem with how TAs can show the skeptic’s doubt to be performatively self-undermining. Stern argues that demonstrating the skeptic’s inability to meaningfully (or coherently) articulate their doubt gives the wrong kind of reason for believing that the skeptic is in fact mistaken.27 But the existence and truth of transcendental beliefs is not established in such a way. Sections 3.1–2 employed modest transcendental arguments and logical inferences to show that the Stroudian conception of objectivity generates an antinomy and that it can only be resolved by distinguishing transcendental from empirical beliefs. The antinomy therefore reveals the conceptual reason for the transcendental status of certain beliefs. It thereby makes transparent why the skeptic has no more to say.
Again, Kant’s metaphor of ‘walking the line’ between an immanent and a transcendent use of concepts can help point the way. If a statement demarcates the ‘limiting line’ for a certain category of concepts, then it is intelligible why that category is inapplicable to such a statement. In establishing the transcendental status of certain beliefs, world-directed TAs retrace this limiting line by stating which truths about the world are necessarily true if there is an independent world at all.
5. Conclusion
The goal of this paper was to rehabilitate world-directed transcendental arguments in the face of Stroud’s famous substitution objection by establishing a dialectical dilemma for the Stroudian skeptic. As the argument of Sections 2–3 has shown, the Stroudian is forced to either (i) outright revoke the generality and a priori certainty of their objection—which at least leads to a stalemate of competing modal intuitions with proponents of TAs and leaves open the possibility that there could be valid TAs which would need to be refuted on a case-by-case basis—or (ii) hold fast to the generality and a priori certainty of their objection but pay the price of inevitably restricting its scope to empirical beliefs while granting that world-directed TAs involving transcendental beliefs about the world are possible. Either way, the debate concerning world-directed TAs is not over and the full-fledged version of Stroudian meta-epistemological skepticism stands refuted.
The first horn of the dilemma was established in Section 2 by showing that no justification of Stroud’s objection which is weaker than a modest TA can suffice. My argument turns on the observation that the intended generality of Stroud’s substitution objection requires a much more substantive and contentious justification than is generally presumed. This shifts the dialectical burden towards the Stroudian skeptic. The required justification is ultimately found in a modest TA which must show that the very ascription of world-directed beliefs presupposes a certain realist conception of objectivity.
To establish the second horn of the dilemma, I first (§3.1) showed that the Stroudian conception of objectivity ends up in the following antinomy: it requires conceiving of the skeptical scenario of global error and also undermines its conceivability. In the second step (§3.2), I argued that the antinomy must be resolved by disambiguating the concept of a world-directed belief as referring to either empirical or transcendental belief. Accordingly, the conceivability of the skeptical scenario pertains to empirical beliefs, its apparent inconceivability to transcendental beliefs. This approach is mandated by the dialectical structure of the argument: the antinomy is generated when the conception of objectivity is made to refer to itself. In the third step (§3.3), I showed that, once the concept of world-directed belief is disambiguated and the antinomy is avoided, the ground for Stroud’s substitution objection has shifted. It can no longer be justified to yield a general skepticism about world-directed TAs, rather, its scope is restricted to empirical beliefs.
In Section 4, I replied to objections to this result. By drawing on Wittgenstein’s analogy of the meter-measure in Paris, I determined the status of transcendental beliefs as neither being merely ‘invulnerable’ in Stroud’s terms nor as merely ‘silencing’ the skeptic without refuting them, but as indeed walking the fine line that demarcates the realm of objectivity.
But which world-directed TAs fit the bill? How can we tell whether they prove the truth of transcendental beliefs or merely the invulnerability of certain general empirical beliefs? This will depend on whether a candidate TA derives necessary conditions for applying the distinctions presupposed by Stroud’s substitution objection, for example, between ‘psychological’ and ‘non-psychological’ propositions. If it is possible to meaningfully put the transcendental status of a belief into question, for example, as something which, though we must believe it to be the case, might still not objectively be the case, then it is not constitutive for stating that something is objectively the case. The challenge thus lies in stabilizing TAs against such self-reflective doubt by arguing for a very strong necessity claim.28 But this challenge does not seem insurmountable and it is, most importantly, a very different challenge from the one posed by Stroud’s substitution objection.
Notes
- On this consensus, see, e.g., Gava (2017) Stern (2019; 2007: 146; 2000: 48). I borrow the classification of Stroud’s skepticism as ‘meta-epistemological’ from Pritchard and Ranalli (2013), it is supposed to highlight that it is a skepticism about an epistemological strategy for securing knowledge claims and not a (first order) skepticism that directly relates to some class of knowledge claims. ⮭
- I am thus following Giladi’s strategy of side-stepping external world skepticism by focusing on how to make transcendental claims (see Giladi 2016), though I try to defend a more ambitious view on the kinds of transcendental claims that can be established using TAs. As Stern notes (2007: 148f.), the hardened external world skeptic would not grant the kind of modal claims and intuitions which seem to be required for world-directed TAs. ⮭
- I am restating the reconstruction due to Bader (2017: 207). ⮭
- The use of Moore’s example is most explicit in Stroud (2011: 137) and (2000a: 170). On Moore’s paradox, see Green and Williams (2007) and Schmid (2017). ⮭
- For the purposes of the present paper, it is irrelevant whether the privileged class is defined with reference to the possibility of language, meaning, thought, or experience. ⮭
- The following section is an extended and modified version of my treatment of Stroud’s skepticism in Schüz (2023: 63–78). ⮭
- “The skeptic distinguishes between the conditions necessary for a paradigmatic or warranted (and therefore meaningful) use of an expression or statement and the conditions under which it is true” (Stroud 1968: 255). ⮭
- Counter-objections to this justification must avoid the other two horns of Stroud’s trilemma. For to claim that warranted assertability is identical to truth means committing oneself to idealism of the anti-realist variety. To alternatively claim that warrant in this case depends on truth seems to require a prior endorsement of verificationism. ⮭
- Cf. Stern’s gloss on the Cartesian cogito (2000: 58). ⮭
- For further discussion, see Section 2.2 and Stern (2000: 46, 59ff). ⮭
- Cf. the description of the privileged class in Stroud (1968: 254): “In general, giving an answer to the question ‘What are the necessary conditions of X?’ does not tell one way or the other about the answer to the question ‘Do those conditions obtain?’ But in the special case of asking for the necessary conditions of there being some language, giving an answer to the first implies an affirmative answer to the second. One’s asserting truly that the truth of S is a necessary condition for there being some language implies that S is true.” ⮭
- See Grundmann and Misselhorn (2003) for this strategy. ⮭
- Cf. Stern’s (2007: 149ff.) critique of Grundmann and Misselhorn (2003). ⮭
- This intermediate step is made explicit in Mizrahi’s critique of transcendental arguments which (in this respect) corresponds to the epistemic appeal to realism considered here, cf. Mizrahi (2017: 740). Another argument against taking conceivability as a guide to possibility is put forth by Stern (2000: 61f). I thank two anonymous reviewers from Ergo for helpful pointers and critical remarks on the issue of conceivability in my argument. ⮭ ⮭
- Cf. The discussion of “constitutive” mind-independence in Burge (2010: 46f.) and of “minimal objectivity” in Peacocke (2009: 739f). ⮭
- Cf. Davidson (1973: 19): “Since charity is not an option, but a condition of having a workable theory, it is meaningless to suggest that we might fall into massive error by endorsing it.” ⮭
- “On that reading it is not possible for all or most of a reasonably comprehensive set of beliefs to be false. So the thought from which the epistemological question is meant to arise would be a contradiction; what it says is possible would not really be a possibility at all” (Stroud 2000b: 197). ⮭
- “I think the source of the philosophical problem of the external world lies somewhere within just such a conception of an objective world or in our desire, expressed in terms of that conception, to gain a certain kind of understanding of our relation to the world” (Stroud 1984: 82). ⮭
- For a detailed gloss on the dimensions in which this core realist claim of mind-independence can be unpacked, see Willaschek (2015: 42–50). ⮭
- So although this conception naturally fits into Moore’s and Sacks’ notion (taken up from Bernard Williams) of an “absolute conception” of the world (cf. Moore 1997: 38f.; Sacks 2000: 312), it can be left open in what sense objective facts need to be non-perspectival and whether this presupposes a “view from nowhere” (cf. the discussion in Nagel 1986: 5–7). However, contra Sacks, the realist element of supposing an “independent ontological base” of representations is not optional on this view (cf. Sacks 2000: 295). ⮭
- The “constitutive transcendental argument” in Peacocke (2009: 741ff.) comes quite close to delivering on (2), although its conclusion of a commitment to “minimal objectivity” would need to be extended to establish (3)–(4). Peacocke notes that his argument does not by itself rule out radical skepticism (2009: 766). ⮭
- Cf. Peacocke’s insightful remarks about positions which have extreme generality being required to deal with self-application (2009: 767). ⮭
- I take this to be the main point of Strawson’s objectivity argument (1966: 57–64) which is refashioned in a more generalized vein by Sacks (2000: 224ff., 254–57). ⮭
- This arguably does not contradict the asymmetry of the relation between truth-maker and truth as the property of a belief (or to the truth of the proposition which is the belief’s content). To see this, consider the analogous existential dependence of secondary qualities on perceivers: although secondary qualities arguably would not exist without perceivers, the content of perceptual states is still primarily determined by the object perceived. ⮭
- Stroud himself admits to such a distinction (2000b: 198, emphasis and insertion are mine): “There is a difference between something’s being inconsistent or impossible (which someone’s believing that it’s raining, and it’s not raining, is not) and something’s being impossible for anyone consistently to believe or discover. If the apparently innocent possibility [i.e., the skeptical scenario of global error] from which the epistemological reasoning would begin is not a possibility anyone could consistently believe to be actual, it can be eliminated from serious consideration right at the beginning.” Cf. the parallel passage in (2000a: 171). ⮭
- This corresponds to Stern’s modal knowledge objection, see fn. 14. ⮭
- See Stern (2017: 18). I am abstracting from Stern’s distinction between ‘retorsive’ and ‘deductive’ TAs here, though for the objection to apply, the antinomy derived in Section 3.1 will have to be viewed as a ‘retorsive’ (performatively self-reflexive) argument against the Stroudian. ⮭
- In Schüz (2023: 119–123) I outline a ‘therapeutic’ methodology for establishing transcendental beliefs as constitutive for our standard of objectivity. ⮭
Acknowledgements
I am grateful to Robert Stern for his generosity and acuity in discussing the first draft of this paper during my research visit at the University of Sheffield. I also thank James Lewis, Mike Stange, and Andrew Werner for comments and help in clarifying fundamental points. I further thank Johannes Haag and his colloquium at the University of Potsdam (especially Anton Kabeshkin and Luz Christopher Seiberth), Adriana Pavic and the Göttingen Mittelbaukolloquium, Gustav Melichar, and Christian Barth for helpful comments on later versions of this paper. In preparing the final version, I greatly benefitted from the detailed comments of three anonymous reviewers for Ergo.
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