## 1. History and Exemplars



Although Immanuel Kant rarely uses the term 'transcendental
argument', and when he does it is not in our current sense (cf.
Hookway 1999: 180 n. 8; cf. Austin 1961), he nonetheless speaks
frequently of 'transcendental deductions',
'transcendental expositions', and 'transcendental
proofs', which roughly speaking have the force of what is today
meant by 'transcendental argument'. Prior exemplars of
such arguments may perhaps be claimed, such as Aristotle's proof
of the principle of non-contradiction (see *Metaphysics*
1005b35-1006a28; Illies 2003: 45-6, Walker 2006: 240 and
255-6); but Kant nonetheless formulated what are generally taken
to be the central examples of such arguments, so the history of the
topic is usually assumed to start here, with the *Critique of Pure
Reason* and its Transcendental Deduction of the Categories, Second
Analogy, and Refutation of Idealism. Briefly put, the Deduction is
directed against Humean scepticism concerning the applicability of
*a priori* concepts to our experience; the Second Analogy
concerns Humean doubts over causal powers or forces; while the
Refutation of Idealism focuses on Cartesian (methodological) doubts
concerning the existence of the external world.



Perhaps because of its brevity and relative clarity, but also perhaps
because of the hope it can be made 'self-standing' and
independent of the (to some) disreputable machinery of transcendental
idealism [see SS3 of the entry on
 Immanuel Kant],
 it is the Refutation that has become the paradigm to many of a
transcendental argument. While the wisdom of this can be questioned
(cf. Bell 1999, where the Refutation is called 'a mistaken
paradigm'), the Refutation undoubtedly makes a useful place for
us to start.



As presented by Kant, the Refutation is aimed at the
'problematic idealism of Descartes', who holds that the
existence of objects outside us in space is 'doubtful and
indemonstrable' (Kant 1781/1787 B274)--where, as Kant
famously remarks in the Preface to the second edition of the
*Critique* in which he comments on the Refutation, 'it
always remains a scandal of philosophy and universal human reason that
the existence of things outside us (from which we after all get the
whole matter for our cognitions, even for our inner sense) should have
to be assumed merely *on faith*, and that if it occurs to
anyone to doubt it, we should be unable to answer him with a
satisfactory proof' (Kant 1781/1787 Bxxxix note). Kant's
strategy in response then sets the canonical pattern for a
transcendental argument, in beginning from what the sceptic takes for
granted, namely that we have mental states which we experience as
having a temporal order, and then arguing for the transcendental claim
that experience of this sort would not be possible unless we also had
generally veridical experience of things in space outside us, and thus
knowledge of the external world. In more detail, the argument can be
presented as follows (cf. Kant 1781/1787 B275-79 and
Bxxxix-xli note):



(1) You are aware of
your inner mental states (thoughts and sensations) as having a
temporal order (e.g., that the sensation of pain you are having now
was preceded in time by a feeling of pleasure).
(2) To be aware of your
mental states as having a temporal order, you must be aware of
something that existed from the time of your previous mental state to
the present.
(3) For that awareness
of permanence to be possible, it is not sufficient to have awareness
of your self (because no permanent self is revealed to us in inner
sense, as Hume argued: see Hume 1739-40: 252) or to have
impressions or representations (because these impressions have a
'perishing existence', as Hume also argued: see Hume
1739-40: 194).


Therefore



(4) The
'permanent' of which you are aware must be something that
is neither you *qua* subject nor your subjective impressions
but must be something distinct from both of these, that is, an object
outside you in the external world.


Therefore



(5) Your awareness of
the external world cannot come from a prior awareness of your
subjective impressions because the latter awareness is not possible
without the former, and so awareness of the external world cannot be
based on the imagination but rather comes from generally veridical
experiences.


In this way, Kant hoped to 'turn the game played by idealism
against itself' (cf. B276), by working from the inner experience
that it takes for granted and showing that this depends on an outer
experience which the idealist doubts, so that in this manner the
'scandal to philosophy' posed by such doubts can finally
be resolved.



However, despite its brevity, the Refutation has given rise to
considerable dispute and discussion, not only because questions can be
raised about the details of the argument, but also because
Kant's wider theoretical commitments to transcendental idealism
have also rendered the Refutation problematic and his intentions
unclear: for example, doesn't the argument undermine
Kant's *own* idealism in some way, and how does the
Refutation relate to the somewhat similar argument in the Fourth
Paralogism of the first edition of the *Critique*
(A366-80), but in which an appeal to transcendental idealism
plays a greater role? These complications have led to a range of
disputes concerning the Refutation, from whether or not it can be made
cogent, to whether or not it fits within Kant's own
philosophical project, and indeed whether focusing on this as
Kant's response to scepticism distorts his conception of
scepticism, and how he thought it should be resolved. (For further
discussion of the Refutation, see Guyer 1987: 279-332, Caranti
2007, Dicker 2008.)



Transcendental arguments found a place in philosophy after Kant,
including in the post-Kantian German idealist tradition (cf. Franks
1999, Franks 2005: 201-59, Taylor 1976, Beiser 2005:
174-91, Rockmore & Breazeale 2014, Nance 2015, Tse 2020,
Schuz 2022; but for some critical discussion of Taylor see Stern
2013 and Houlgate 2015, and of Beiser see Stern 2012). However, their
prominence in more contemporary analytic philosophy is largely due to
the work of P. F. Strawson, and particularly his earlier books
*Individuals* and *The Bounds of Sense*--the latter
of which is a commentary on Kant's *Critique*, while the
former is written under its influence in a broader way (cf. Grundmann
1994; Niquet 1991; Callanan 2011). One example from these works is the
'objectivity argument' to be found in *The Bounds of
Sense*, which aims to show that '[u]nity of diverse
experiences in a single consciousness requires experience of
objects'; the argument may be outlined as follows (see Strawson
1966: 97-112, esp. 108; also see Cassam 1997, Cheng 2021a):



(1) Being
self-conscious is a matter of being able to ascribe diverse
experiences to oneself, while being conscious of the unity of that to
which they are ascribed.
(2) To be in a position
to think of experiences *as* one's own, one must be able
to think of them *as* experiences.
(3) For experience to
be such as to provide room for thought of experience itself, it must
provide room for a distinction between 'This is how things
are' and 'This is how things are experienced as
being'.
(4) Only experience of
objects that are subject-independent could provide room for this
is/seems distinction.


Therefore



(5) Subject-independent objects exist.


In this way, Strawson hoped to capture what he took to be the central
core of Kant's position, but without appeal to the
'doctrines of transcendental psychology' (Strawson 1966:
97), which he found to be problematic. Likewise, in
*Individuals*, Strawson presented an argument starting from the
premise that we think of the world as containing objective particulars
in a single spatiotemporal system, to the conclusion that objects
continue to exist unperceived, where the latter is said to be required
in order to make possible the kind of identification and
re-identification necessary for the former (cf. Strawson 1959:
31-58). Thus, as Strawson famously put it, the sceptic
'pretends to accept a conceptual scheme' of a world
containing objects in a spatio-temporal system, 'but at the same
time quietly rejects one of the conditions of its employment'
(Strawson 1959: 35).



On the basis of the promise of arguments of this sort from Strawson,
and from others (such as Shoemaker 1963: 168-9), together with
growing interest in the work of Kant himself within analytic
philosophy, this period of the late 1950s and early 1960s was a
significant one for the history of transcendental arguments, leading
to much subsequent discussion. At the same time, central
Wittgensteinian doctrines prominent at the time (such as the notion of
'criteria': see SS1.3 of the entry on
 other minds)
 were also given a transcendental inflection, so certain
Wittgensteinian claims came to take on the form of transcendental
arguments (cf. Rorty 1971: 3, where he comments that 'Many
admirers of Wittgenstein's *Philosophical Investigations*
and of Strawson's *Individuals* have taken the theme of
both books to be an analysis of philosophical skepticism and their
distinctive contribution to be a new way of criticizing the
skeptic'). However, crucial to the debates of the period were
also a number of critical articles pointing to the perceived
limitation of the transcendental approach, including those by Stefan
Korner (Korner 1966, 1967, 1969) and by Barry Stroud (Stroud
1968), where the latter in particular shaped the ensuing discussion
over the value of transcendental arguments and what they could be
expected to achieve, as we shall see in
 section 3.



Nonetheless, while the intervention by Stroud and others led to doubts
about the value of transcendental arguments, as theorists asked if
these critiques held good and if so what might remain of the
transcendental approach, this did not deter prominent philosophers
continuing to produce transcendental arguments. Two of these may serve
as further exemplars of the genre, where both have gone on to be much
discussed. The first was offered by Hilary Putnam in relation to
external world skepticism once again, and the second by Donald
Davidson, this time relating more directly to the problem of other
minds.



Putnam's argument comes in Chapter 1 of *Reason, Truth and
History*, where his goal is to refute a modern-day version of
Descartes' evil demon hypothesis, according to which I do not
inhabit a world containing ordinary physical objects (trees, tables,
houses), but I am a brain in a vat in a lab whose experiences are
caused by a computer artificially stimulating my nerve endings, so
that none of these objects actually exist beyond my hallucinatory
impression of them (see the entries on Brains in a Vat and
Skepticism and Content Externalism). This is the brain-in-a-vat
hypothesis, and it stands for the possibility that, for all I know,
nothing rules out the world being very different from how it appears
to me to be, given the gap that exists between appearance (our
experience of it) and reality.



Now, Putnam's response to the sceptic is to argue that though we
cannot rule out the possibility that we are brains-in-vats on the
grounds of how things appear to us, we can rule it out nonetheless.
How? Here is one reconstruction of the reasoning: we can rule it out
because on a plausible theory of reference, it is self-refuting: that
is, 'I am a brain-in-a-vat [or BIV, for short]' cannot be
truly affirmed by anyone. The theory of reference Putnam uses as a
premise is a causal one, which states that 'one cannot refer to
certain kinds of things, e.g., *trees*, if one has no causal
interaction at all with them, or with things in terms of which they
can be described' (Putnam 1981: 16-17). Putnam defends
this theory, on the grounds that it alone can explain how reference
occurs in a way that is not 'magical', i.e., which does
not assume that the connection is just somehow intrinsic between
representations and their referents. It then follows, according to
Putnam, that a BIV affirming 'I am a BIV' is saying
something true only if the BIV is in what the BIV is calling a
'vat'. But the BIV is not in one of those; rather, he is
in a *real* vat. What he is calling a 'vat' is that
to which his use of that term causally connects in a referential
way--where for a BIV, that is something in the computer that
prompts his applications of 'vat' by giving him
hallucinations of the appearance of vats. Yet the BIV is not in that
part of the computer. Thus, Putnam concludes, 'I am a BIV'
cannot be truly asserted by anyone, much like 'I do not
exist' or 'I cannot construct a meaningful sentence'
(cf. Bardon 2005). It therefore cannot ever be wrong to assert that
one is not a BIV, so that in this sense 'I am not a BIV'
is an incorrigible claim (cf. Putnam 1981: 14-15). Putnam
therefore holds that we can rule out the BIV hypothesis on *a
priori* grounds, and thus refute the sceptic.



Putnam is keen to emphasise the transcendental nature of his
enterprise in this respect. He stresses that the kinds of constraints
on reference that operate here and disprove the BIV hypothesis are not
physical or merely analytic, but involve limitations on what is
possible that can be arrived at through philosophical reflection on
the nature of representation and meaning, and hence fit into a broadly
Kantian model of how to respond to scepticism, albeit with more
empirical elements:



> 
> What we have been doing is considering the *preconditions* for
> *thinking about, representing, referring to*, etc. We have
> investigated these preconditions *not* by investigating the
> meaning of these words and phrases (as a linguist might, for example)
> but by *reasoning a priori*. Not in the old
> 'absolute' sense (since we do not claim that magical
> theories of reference are *a priori* wrong), but in the sense
> of inquiring into what is *reasonably* possible
> *assuming* certain general premisses, or making certain very
> broad theoretical assumptions. Such a procedure is neither
> 'empirical' nor quite 'a priori', but has
> elements of both ways of investigating. In spite of the fallibility of
> my procedure, and its dependence upon assumptions which might be
> described as 'empirical' (e.g., the assumption that the
> mind has no access to external things or properties apart from that
> provided by the senses), my procedure has a close relation to what
> Kant called a 'transcendental' investigation; for it is an
> investigation, I repeat, of the *preconditions* of reference
> and hence of thought--preconditions built in to the nature of our
> minds themselves, though not (as Kant hoped) wholly independent of
> empirical assumptions. (Putnam 1981: 16)
> 



As a result of his attempt to respond to external world scepticism in
this way, Putnam has had an important influence in reviving interest
in the possibility of using transcendental arguments against
scepticism. (For further discussion of Putnam's position, see
Brueckner 1986, Coppock 1987, Heil 1987, David 1991, Brueckner 1992,
Caranti 2007: 110-13.)



Finally, we may turn to the work of Donald Davidson, who like Putnam
bases his transcendental claim on a form of externalism, which links
the content of our mental states to how we relate to our environment;
but in his case, this idea is directed against scepticism concerning
other minds. Thus, while the sceptic holds that the existence of such
minds is doubtful, Davidson argues that it would not be possible for a
creature like me to have thoughts unless I lived in a world with other
creatures who also had thoughts, so the truth of the latter can be
deduced from the fact that I am indeed capable of thinking:
'What are the conditions necessary for the existence of thought,
and so in particular for the existence of people with thoughts? I
believe there could not be thoughts in one mind if there were no other
thoughtful creatures with which the first mind shared a natural
world' (Davidson 1989: 193; note that he uses
'existence,' not 'possibility'). On one
interpretation, Davidson's transcendental argument is based on
his account of what it takes for a thought to have content, for which
he argues that a process of 'triangulation' must occur,
whereby the content of the thought someone is having is
'fixed' by the way in which someone else correlates the
responses he makes to something in the world. Thus, Davidson argues,
if there were no other people, the content of our thoughts would be
totally indeterminate, and we would in effect have no thoughts at all;
from the self-evident falsity of the latter, he therefore deduces the
falsity of the former (cf. Davidson 1991: 159-60). Davidson
therefore argues that the mistake the sceptic makes, in common with
the Cartesian heritage of which he is part, is in the assumption that
it is *possible* to be a lone thinker: Davidson's
transcendental argument is designed to show that this is not in fact
the case, given the constraints on what it takes to have thoughts with
content, so that the existence of a single thinking subject entails
the existence of others.



As Davidson suggests (cf. Davidson 1991: 157), his position here might
be said to have certain similarities to that put forward in
Wittgenstein's Private Language Argument, at least under the
interpretation given by Kripke (see Kripke 1982). Kripke takes
Wittgenstein as arguing that it is impossible to make sense of what it
is to follow a rule correctly, unless this means that what one is
doing is following the practice of others who are like-minded: what
makes our continuation of some addition rule a case of rule-following
at all (for example), is that the community goes on in the same way;
and, unless addition were rule-governed as a practice, statements like
'2+2=4' could have no meaning. Thus, from the fact that we
are able to make such statements meaningfully, the existence of a
community of others that 'fix' this rule can be inferred,
as a necessary pre-condition for the former (cf. Kripke 1982: 89). On
this view, then, unless the sceptic is prepared to admit the existence
of this community of fellow-speakers, and thus attribute a capacity
for intentional rule-following to those around him, he cannot make
sense of the idea of meaningful thought in his own case.



We have therefore seen that taking their inspiration from Kant to a
greater or lesser degree, philosophers have come to develop a range of
transcendental arguments that are intended to refute scepticism in a
robust and ambitious manner, by establishing anti-sceptical
conclusions on the basis of transcendental claims. From these
exemplars and others, therefore, we may now say something further
about how such arguments work and what makes them distinctive.


## 2. Key Features of Transcendental Arguments



From something like the canon of transcendental arguments outlined
above, the characteristic marks and the significance of such
arguments might be listed as follows:



1. Transcendental arguments are typically anti-sceptical, so that (as
Strawson puts it) it is widely assumed that 'the point of
transcendental arguments in general is an anti-sceptical point'
(Strawson 1985: 10). Moreover, in the ambitious form in which we have
considered them so far, they refute the sceptic in a direct manner, by
purporting to prove what she doubts or questions, and they do so on
their own, without bringing in any wider epistemological theories or
considerations. And these arguments are what is sometimes called
*world-directed* or *truth-directed*, as opposed to
*self-directed* (cf. Peacocke 1989: 4; Cassam 1997: 33; Cassam
1999: 83): that is, they set out to establish the truth of some claim
about how reality is and what it contains (such as subject-independent
objects in space and time, or other minds, or causal laws).



2. Because of their anti-sceptical ambitions, transcendental arguments
must begin from a starting point that the sceptic can be expected to
accept, the necessary condition of which is then said to be something
that the sceptic doubts or denies. This will then mean that such
arguments are ineffective against very radical forms of scepticism,
which doubt the laws of logic, and/or which refuse to accept
*any* starting point as uncontentious; and it will also mean
that they may be effective against a sceptic who is prepared to accept
some starting point, but then ineffective against another sceptic who
is not. But neither of these features of transcendental arguments need
be felt to be disabling: for the scepticism of the radical sceptics is
perhaps of dubious coherence, or at least of little interest because
they seem so unwilling to engage with us, while the second limitation
may mean merely that different transcendental arguments are required
for different sceptical audiences.



3. Because of the need to find an uncontentious starting point,
transcendental arguments will also then characteristically be first
personal, by beginning from how *I* or *we* experience,
think, judge, and so on. Thus, while it is perhaps reasonable to hold
that there are necessary conditions for the possibility of
'extra-personal' entities such as material objects,
substances, the universe, time and so on, a transcendental argument
which is directed against scepticism is unlikely to be concerned with
exploring such conditions, as the sceptic is unlikely to admit the
existence of the things to which the conditions belong.



4. Transcendental arguments involve *transcendental claims*, to
the effect that *X* is a necessary condition for the
possibility of *Y*, where in saying this, the arguments do not
assume this to be a matter of merely causal, natural, or nomological
necessity. Given that their target is the sceptic who challenges our
claims about the world, there are clearly two good reasons for this.
First, although our observation of the world might suggest that
experience has certain necessary causal conditions (e.g., light and
sound must be transmitted between particular wavelengths), we can
hardly use such considerations against a sceptic of this sort, for
whom all such empirical knowledge is in question, and against whom we
are therefore required to adopt a position that is less open to doubt
in this way. Second, if the transcendental argument's claim is
one of only natural necessity, then this allows that there are
metaphysically possible worlds (for example, where the laws of physics
do not hold) in which this claim is false, again opening us up to the
sceptical challenge of showing we are not in such a world.



5. However, if the transcendental claims involved are not a matter of
merely causal or natural necessity, this then raises the question of
what form of necessity they *do* in fact involve. If they were
true in virtue of their meaning alone (even if unobviously so), and
thus analytic, then the necessity might be said to be purely logical,
where to deny the claim is then to assert some form of logical
contradiction (cf. Bennett 1979, Walker 1978: 18-23, Walker
1989: 63-4, Bell 1999). Assuming that the problematic
analytic/synthetic distinction is viable, this may still not seem
to be the case in many instances of such transcendental claims, where
in fact they may be said to be synthetic *a priori* (cf.
Wilkerson 1976: 199-213). To many, nonetheless, it has appeared
that the transcendental claim is not a logical necessity, but stands
somewhere between that and natural necessity, perhaps putting it into
the camp of *metaphysical* necessity, as this is sometimes
understood: that is, a necessary relation which holds not by virtue of
logical or causal constraints on the nature of logical or physical
possibilities, but by virtue of metaphysical constraints on how things
can be--much as the fact that nothing can be red and green all
over is arguably not determined by any law of logic or causal law, but
the nature of colour, and how it can be exemplified in things. There
will be more on this in section 5 below.



6. It is then partly because of the apparently rather special nature
of these transcendental claims, that the suspicion arises that there
will then turn out to be something distinctively Kantian about such
arguments; for Kant made it the focus of his critical project to
account for metaphysical knowledge of this sort, where transcendental
idealism is then supposed to provide the answer to how such knowledge
is possible. The idea, roughly speaking, is that it is too much for us
to be able to know how things must be beyond the limits of our
experience, and so claim metaphysical knowledge of
things-in-themselves. By contrast, once we confine ourselves to how
things appear to us given our ways of seeing and thinking about the
world, then we can understand how we could at least acquire knowledge
of how things must behave as phenomena, by knowing about the forms of
intuitions and concepts through which such phenomena must appear to us
if we are to experience them at all (cf. Williams 1974, Pippin 1988,
Stroud 1999, Stroud 2000a). However, as we saw in the case of
Strawson, whether or not such full-blooded Kantian commitments are
necessary to the transcendental argument strategy is a matter of
dispute. Indeed, some have argued that there is a 'neglected
alternative' here: namely, while Kant might be right to hold
that we cannot plausibly claim insight into the constraints on the
world itself but only on the nature of our sensibility and
understanding, nonetheless we can argue from this that the world must
itself be a certain way to fit these conditions, without thereby
thinking that it is mind-dependent or that all we thereby know is how
things appear to us. The analogy is thus drawn to a case such as the
following: once we know how our lungs work, we can know what the air
must be like in order to allow us to breath, without the nature
of air being determined by how our lungs work (cf. Harrison 1989,
Westphal 2004: 68-126).



The features discussed above therefore have a reasonable claim to be
what make transcendental arguments distinctive, at least of the sort
we have considered so far. However, as we shall now go on to see,
transcendental arguments of this type have turned out to be open to
serious objections, so that alternative models have been proposed
which do not incorporate all these features in quite the same way.


## 3. Objections to Transcendental Arguments



Just as the rise in interest in transcendental arguments within
twentieth-century philosophy can largely be traced back to the work of
Strawson, so too the subsequent disillusionment can largely be traced
back to the work of one person, namely Barry Stroud, in his
influential 1968 article (Stroud 1968). In that paper, Stroud focused
on the nature of the transcendental claim that the truth of some
proposition *S* is a necessary condition for the possibility of
language, but then argued that 'the sceptic can always very
plausibly insist that it is enough to make language possible if we
*believe* that *S* is true, or that it looks for all the
world as if it is, but that *S* needn't actually be
true' (Stroud 1968 [2000b: 24]). Moreover, the general problem
this raises is that if such a response by the sceptic is plausible in
the case of language, perhaps it is also plausible in the case of
other starting-points too? Thus, for example, when it comes to
scepticism about the existence of the external world or other minds,
maybe no argument can be constructed to show there must actually
*be* such a world or minds as a condition for inner experience
or the having of thoughts, but just that we must believe them to
exist, or that they must seem to us to do so--which hardly looks
like enough to quash sceptical doubts on these matters.



Now, in the 1968 paper, Stroud appears to get to his conclusion by
arguing from an analysis of specific cases (viz. arguments proposed by
Strawson and Shoemaker in Strawson 1959 and Shoemaker 1963
respectively). But then, this may seem to leave open the hope that
even if these arguments fall to his critique, others may not. However,
in subsequent work, Stroud has said more to substantiate his objection
and make it seem more likely to hold across the board. For, while he
allows that we might reasonably be able to make modal claims about
'how our thinking in certain ways necessarily requires that we
also think in certain other ways', he believes it is puzzling
'how...truths about the world which appear to say or imply
nothing about human thought or experience' (for example, that
things exist outside us in space and time, or that there are other
minds) '[can] be shown to be genuinely necessary conditions of
such psychological facts as that we think and experience things in
certain ways, from which the proofs begin'. Stroud goes on:
'It would seem that we must find, and cross, a bridge of
necessity from the one to the other. That would be a truly remarkable
feat, and some convincing explanation would surely be needed of how
the whole thing is possible' (Stroud 1994 [2000b: 158-9;
cf. also 212]). Thus, Stroud is prepared to allow 'that we can
come to see how our thinking in certain ways necessarily requires that
we also think in certain other ways, and so perhaps in certain other
ways as well, and we can appreciate how rich and complicated the
relations between those ways of thinking must be' (Stroud 1994
[2000b: 158-9]); but he believes that anything more than this,
which asserts that 'non-psychological facts' about the
world outside us constitute necessary conditions for our thinking, is
problematic.



Then, having apparently established that the strongest defensible
transcendental claims concern merely how things must appear to us or
what we must believe, the second stage of Stroud's argument is
that in order to bridge the gap that this has opened up, and to get to
a conclusion about how things actually *are*, one must opt
either for verificationism or idealism. The former holds that in order
to be meaningful, a sentence must say something that we can determine
to be true or false. If so, then we cannot be left in the limbo of
sceptical doubt behind a veil of appearances wondering where the truth
lies. The latter sees no gap between how the world is and how we think
things are or merely appear to us. However, aside from the potentially
problematic nature of both these positions, an appeal to either
verificationism or idealism is also dialectically unsatisfactory, as
any such appeal would appear to render the transcendental argument
itself redundant--for each on its own is powerful enough to
disarm sceptical worries, without the transcendental manoeuvre now
being required (cf. Stroud 1968 [2000b: 24-5]). In this way,
Stroud has convinced many that the proponent of transcendental
arguments faces an unattractive dilemma: either to dispense with
verificationism or idealism, but fall short of the anti-sceptical
conclusion concerning how things are; or to accept verificationism or
idealism, but then make the transcendental argument itself
superfluous.



The problem that Stroud has highlighted may be briefly illustrated by
returning to the exemplars of transcendental arguments that we
considered in
 Section 1.
 Thus, when it comes to Kant's Refutation of Idealism, it can be
said that the most that Kant really establishes is that we have
experience *as of* things outside us in space, while all that
Strawson's objectivity argument shows is that we must
*apply* the is/seems distinction to our experience, and so
believe that things exist without us experiencing them, but that this
doesn't do enough to show that this distinction is really a
valid one (cf. Wilkerson 1976: 57, Brueckner 1989). Likewise, against
Putnam it is argued that the sceptic can challenge his externalist
theory of reference, where on a more internalist view, you could then
think about being in a vat even if you were in one, as the meaning of
'vat' no longer depends on your relations to the world;
or, if Putnam insists on his externalism, it could be claimed that
this is *already* a position that rules out scepticism because
it assumes that the mind and world are linked in important ways,
making it unnecessary to make appeal to the specific transcendental
argument that Putnam rests upon it (cf. McCulloch 1999). Similarly,
against Davidson it can be argued that thought would be possible, even
if the 'others' with which one 'triangulated'
were nothing but robots or automata; or again, if this is ruled out by
appeal to some form of semantic externalism, this then renders the
transcendental argument redundant. In all these cases, therefore, it
may appear that Stroudian objections can be used to damaging
effect.



Thus, applying Stroud's concerns to a range of arguments in this
way may seem to support the view that the transcendental arguments so
far produced succumb to his dilemma (although, of course, attempts to
bolster the arguments can also be made). Nonetheless, it might be felt
that unless Stroud can substantiate his more principled objection to
the very possibility of crossing the 'bridge of necessity'
that is required by any sort of world-directed transcendental claim,
he has still not yet established conclusively that no transcendental
argument can be made to work, and must always either fall short or end
up being superfluous. So the question arises: how powerful is his
suggestion that a 'truly remarkable feat' is required
here, one that we have good reason to think cannot feasibly be
accomplished?



Perhaps one difficulty that can be raised for Stroud, is that while he
thinks there is something inherently problematic in making a claim
about how *the world* must be as a condition for our thought or
experience, he does not think that there is anything particularly
problematic about claiming that our thought or experience is a
necessary condition for some other aspect of our thought or
experience--indeed, he exploits such claims himself in his own
arguments against the sceptic (cf. Stroud 1994 [2000b:
165-76]). But how can claims of necessary connections between
some thoughts or experience and some others be defended more cogently
than claims of necessary connections between some thoughts or
experience and the world? Why are such 'bridges' or modal
connections easier to make 'within thought' than between
how we think and how the world must be to make that thought possible?
Now, one might take this symmetry between the two to be reason to be
suspicious of claims of necessary connections both between some
thoughts and the world and between some thoughts and other thoughts
about the world: but as we have seen, Stroud himself seems to think
they are viable between 'psychological facts' (cf. Stroud
2000a [2000b: 224-44]). If so, it could be argued, he needs to
give us some account of why they are less problematic here than
between our thought and the world; but in fact he just seems to take
it to be obvious, and so provides no such account (cf. Cassam 1987:
356-7; Glock 2003: 38-9).



However, even if Stroud's position is indeed weaker than it may
at first appear, this does not mean that transcendental arguments are
in the clear when it comes to the world-directed transcendental claims
they embody. For, a different worry to the same effect can also be
urged against them, which in this case relates to the dialectics of
our engagements with scepticism (cf. Stern 2007). The central thought
is this: On the one hand, the sceptic is often conceived as grounding
her doubts on the fallibility of our ordinary belief-forming
processes, such as perception and memory. On the other hand, the
proponent of a transcendental argument hopes to answer her doubts by
advancing the claim that *X* is a necessary condition for the
possibility of *Y* and so deduce the former from the latter.
But the dialectical concern this raises is this: why, if the sceptic
is dubious about cognitive methods like perception and memory, should
she be any more sanguine about the methods we have used (whatever
these are) to arrive at the modal claims embodied in the
transcendental argument?



Now, one line of response might be to say that the doubts the sceptic
raises over our modal knowledge here can themselves be blocked or
shown to be spurious, for example, by providing evidence for the
reliability of our methods in the modal case, or questioning the right
of the sceptic to use the mere possibility of error against such
knowledge. But then, it seems likely that similar claims could
*also* be used to bolster the credentials of our
*non*-transcendental bases for knowledge, such as perception
and memory, in a way that would then render the transcendental
argument redundant.



Thus, even if Stroud's own critique of transcendental arguments
is found wanting, it seems that another along these lines can be put
in its place, leading to a similar dilemma: either transcendental
arguments are offered to try to establish what the sceptic questions,
but are then vulnerable to sceptical doubts concerning the truth of
the modal claims they employ; or they can successfully respond to
those doubts, but in ways that then seem likely to render our
non-transcendental grounds for knowledge legitimate too, so that our
conviction concerning such knowledge no longer seems to need to make
any appeal to a transcendental argument.



One further thought is that perhaps the main problem is a consequence
of mistakenly supposing that transcendental arguments should be
deductively valid. Note that Kant himself used the corresponding
German phrase of 'deduction' in a different sense (see the
entry on Kant's Transcendental Arguments). One possibility is
that such arguments should be taken as *abductive* ones,
involving inference to the best explanation (Hoffmann 2019, Allen
2021, Reynolds 2022): the idea is that although one cannot deductively
infer *X* from the possibility of *Y*, one can claim
that *X* is the best explanation of *Y*'s being
possible. In making such an inference, one needs to list various
candidate explanations and give good reason to think that the
one being favored is indeed the best explanation. If this path is
taken, it might engender worries about the distinctness and power of
transcendental arguments. In the next section we will see more
responses to the above objections.


## 4. Responses to Objections



While it would be premature to say that attempts to construct
ambitious world-directed transcendental arguments have been entirely
abandoned (see e.g., Peacocke 1989, Grundmann & Misselhorn 2003),
nonetheless the most common way of responding to these Stroudian
difficulties has been to re-think how transcendental arguments might
be best used, and to come up with strategies that are in various ways
more modest than those we have discussed so far. What characterises
such modest responses is the idea that Stroud is indeed *right*
that all we can really substantiate by way of a transcendental claim
is how things must appear to us or how we must believe them to
be--but then attempt to make this weakened claim do some
anti-sceptical work. We will briefly consider four such responses: one
from Strawson's earlier work; one from his later writings; one
from Stroud; and one from Stern 2000. (For other recent examples of
less ambitious transcendental arguments, see Chang 2008 and Massimi
2014; also see Coates 2017 on Strawson 1962).



The first response takes its inspiration from a re-consideration of
the Strawsonian transcendental arguments that were criticised by
Stroud, but offers a different interpretation of them in the light of
that critique. Thus, it is suggested, the mistake is to see
Strawson's argument as straightforwardly world-directed in the
way that it was presented earlier, as offering a direct response to
the sceptic by proving what the sceptic doubts. Rather, it is said,
the strategy is more like Aristotle's elenchic response to the
sceptic who doubts the principle of non-contradiction: namely, to show
that her doubts cannot be intelligibly stated or expressed, as
acceptance of this principle is a necessary condition for having
meaningful thought at all. Likewise, therefore, it can be suggested
that Strawson intended his transcendental approach to operate in the
same way, where (as Strawson puts it) '[the sceptic's]
doubts are unreal, not simply because they are logically unresolvable
doubts, but because they amount to the rejection of the whole
conceptual scheme within which alone such doubts make sense'
(Strawson 1959: 35; cf. also 106 and 109, and also Glock 2003:
35-6 and Illies 2003: 44-56). Thus, it may seem, a modest
transcendental claim is all that we require, to the effect that the
sceptic cannot raise a doubt to challenge us here, given what she must
believe in order for her to think or utter anything intelligible at
all. The transcendental argument is effective, therefore, not by
showing that what the sceptic doubts is false, but by showing that
those doubts have violated the conditions of meaningfulness, and thus
require no positive answer or response.



Now, whether or not this is the most charitable way of reading
Strawson's earlier position, he himself does not seem to have
adopted quite this first response when he came to reply to Stroud in
his later work. Rather, while he accepts Stroud's insistence
that the transcendental claim must be weakened (cf. Strawson 1985: 9),
he then also offers what he call a *naturalistic* reply to the
sceptic based on Hume and also on some Wittgensteinian ideas developed
in *On Certainty*, according to which the right approach to
sceptical doubts is not to try to answer them with an argument, but to
show them to be 'idle', as unable to shift those core
beliefs which are implanted in us by nature or which lie at the centre
of our ways of thinking (cf. Strawson 1985: 13). Here, then, the
approach is not about the meaninglessness or unintelligibility of
sceptical doubt (as on the first response), but on its inability to
shift or dislodge our beliefs because of their embeddedness within our
thinking (where semantic issues need not be the only consideration in
rendering them embedded in this way). Within this naturalistic
approach, therefore, Strawson suggests that transcendental arguments
can do valuable work, in precisely helping us to show the sceptic that
some beliefs are fundamental to us in this way, and thus impervious to
sceptical doubt just as the naturalist claims--but where to play
this role, the transcendental claim only has to be a modest one,
concerning what we must believe, not how things are (cf. Strawson
1985: 21-23; see also Grayling 1985 and Callanan 2011).



A third type of modest approach is offered by Stroud himself, where he
claims that even a transcendental argument which shows what we must
believe can have anti-sceptical value, in showing that these beliefs
are *indispensable* and *invulnerable*, in the sense
that we not only cannot abandon them, but also we cannot find them to
be false in ourselves or others, because to so find them would be to
give up believing anything at all. However, Stroud allows that this
sort of status for the belief in question--for example, the
belief that there are enduring particulars, or other minds--does
not go as far as ruling out the possibility that belief of this sort
are in fact not true (see Stroud 1994, 1999).



Finally, in Stern 2000, it is argued that modest transcendental
arguments can be shown to be useful against scepticism, once we
distinguish sufficiently carefully between the kinds of scepticism
there are, and go for the right target or targets--where a less
demanding form of scepticism may perhaps be defeated by a less
ambitious transcendental claim. So, for example, if we take the target
to be a sceptic who demands certainty, then a modest transcendental
argument will not suffice. But if we take the sceptic to be one who
demands merely justification that may nonetheless be fallible, and who
claims we do not have even this because our beliefs are not properly
supported by our generally accepted cognitive norms, then (it is
claimed) a modest transcendental argument can indeed be useful. So,
for example, the justificatory sceptic may claim that our belief in
other minds seems to be grounded on nothing but the link between
behaviour and mentality that we observe in our own case; but then, she
can argue, it is based on little more than a poor argument from
analogy, which we are not properly warranted in extending to others,
as we are arguing from only a single instance (viz., ourselves), which
is an inadequate inductive base on which to reason in this way. In
response, however, it could be argued that unless others appeared to
us as more than mere bodies, but instead as persons with minds, we
could not acquire the capacity to apply mentalistic predicates to
ourselves, and thus become self-conscious. This argument remains
'modest' because its transcendental claim extends only to
how others must appear to us, and so is not
'world-directed' in the manner of more ambitious
transcendental arguments; but even so, the idea is, it is still
sufficient to show that our belief in these other minds is not merely
based on a faulty inference in the way that the justificatory sceptic
supposes, but rather on the nature of our experience--where as
such, it can therefore be used to show that this belief is warranted,
even if it could still be false.



Now, none of these approaches is unobjectionable, and it remains to be
seen which, if any, is to be preferred. Concern about the Aristotelian
approach can relate to whether it can show that belief in *X*
is necessary for intelligible thought *in general*, or for
thought by creatures *like us*--where if it only
establishes the latter, the possibility of a sceptic raising
intelligible doubts about it would seem to remain, while establishing
the former seems extremely demanding if not impossible (cf.
Korner 1967). Further, the worry might be raised in a Stroudian
spirit, that all this approach shows is that doubts cannot be
coherently expressed concerning *X*, but where that then seems
to fall short of establishing that *X* is really the case. And
finally, while it may perhaps seem right to say that there is
something unintelligible or meaningless about questioning the
principle of non-contradiction (although this can also be challenged:
cf. Priest 1987), other sceptical doubts do not seem problematic to
the same degree. (For further discussion points of this sort, see
Illies 2003: 54-63.) Along similar lines, critics have also
questioned Strawson's naturalistic approach, as not fully
answering the sceptical challenge: for even if a doubt here is
'idle', it does not follow that what is questioned is
really true (cf. Valberg 1992: 168-96, Sen 1995). Likewise, when
it comes to Stroud's position, as he himself admits, the
indispensability and invulnerability he speaks of 'might not
seem like much reassurance in the face of a general scepticism'
(Stroud 1999: 168), given that it not only does not rule out the
possibility of falsity, but also seemingly gives no additional reasons
for taking that possibility less seriously. Moreover, it has been
suggested that Stroud's position is unstable, as the claim that
certain beliefs are invulnerable on the one hand, and the acceptance
that they might be untrue on the other, seem to stand in tension with
one another (see Brueckner 1996). The position proposed in Stern 2000
tries to get round these difficulties, but has also been accused of
ducking important aspects of the sceptic's challenge (see e.g.,
Sacks 1999 and 2000: 276-85; and for Sack's own positive
proposals, see Sacks 2005a, 2005b and 2006). Finally, for an attempt
to adopt an approach that is neither ambitious or modest, but
somewhere between the two, see McDowell 2006.



Whatever their respective strengths and weaknesses, one thing these
modest strategies have suggested is that some of the central features
of transcendental arguments outlined above do not fit arguments of
this less ambitious sort. Thus, these arguments are not
world-directed, but are self-, experience-, or belief-directed.
Secondly, they do not expect the transcendental arguments to refute
the sceptic on their own (as it were), but in conjunction with broader
epistemological or anti-sceptical considerations (such as naturalism,
or perceptual and other epistemic norms). Thirdly, by offering an
approach that is more modest, they raise the question of how much
adequate responses to scepticism are entitled to assume and what kinds
of reassurance they are meant to provide (cf. Hookway 1999; Cassam
2007: 51-84; Wang 2012). And in all these ways, they have raised
exegetical issues about how Kant's place in the canon discussed
above might be understood differently, concerning his attitude to
scepticism and whether in the end his intentions are best interpreted
in 'modest' or more ambitious terms (cf. Callanan 2006;
Bardon 2006; Stapelford 2008).


## 5. Connections to Modal Metaphysics and Epistemology



In listing key features of transcendental arguments in section 2, it
was indicated that *metaphysical* necessity might be the right
kind of modality for transcendental arguments, and this brings the
discussion to the realm of modal metaphysics. To begin with, if one is
sceptical about modality anyway (Quine 1953), then using modality to
understand transcendental arguments is a non-starter. However, if one
is comfortable with modality in general, it is then a natural way to
analyse transcendental arguments. After all, transcendental arguments
can be seen as offering certain kind of *philosophical
explanation*--'transcendental explanation', as
it is sometimes called--and given this, metaphysical
explanations of various sorts are natural candidates. More
specifically, with our schema above, we should say that *X*
transcendentally explains the possibility of *Y*, or more
succinctly, *X* possibilitates *Y*, and this relation
should be understood with metaphysical modalities. This picture is not
universally shared: some hold that in answering transcendental
how-possible questions, identifying the necessary conditions for the
targets is explanatorily idle (Cassam 2007).



Modal metaphysics is itself a difficult area that involves all kinds
of sophisticated theories, such as realism, ersatzism, fictionalism,
to name just a few (see entry on varieties of modality). Fortunately,
to analyse transcendental arguments with metaphysical modality, there
is no need to commit to any theory of the nature of metaphysical
necessity. In effect, what is more relevant is modal epistemology;
more specifically, how one manages to know whether a given modal claim
is true or not. To see how this is so, let's use this toy
example:



> 
> Kantian categories are necessary conditions for the possibility of
> objective cognition.
> 



We will use "Kantian categories" as a placeholder for any candidates
for being the relevant conditions. To analyse this with metaphysical
necessity, this statement can be paraphrased as follows:



> 
> It is metaphysically necessary that if there is objective cognition,
> then Kantian categories are in place.
> 



Now, how do we know, or at least try to figure out, the truth or
falsity of such a statement? This is where modal epistemology enters
the scene. As with many other areas in philosophy, the territory is
often divided into rationalism and empiricism, though admittedly such
division can also miss the subtleties among different views. In any
case, one major view within the rationalist tradition is the
*conceivability* approach (Yablo 1993; Chalmers 1996, 2010).
According to such an approach, knowledge of the above statement about
metaphysical necessity is based on knowledge of the following:



> 
> It is inconceivable that there is objective cognition without there
> being categories in place.
> 



The rationale for this move is that according to such an approach,
conceivability is a guide to metaphysical possibility, while
inconceivability is a guide to metaphysical impossibility. Given this,
if it is metaphysically necessary that if A then B, then it is not
metaphysically possible that there is A without B. Now it is natural
to expect that the difficulties with the conceivability approach will
thereby translate into this rendering of transcendental arguments, in
roughly this way: this rendering assumes that inconceivability entails
metaphysical impossibility, but such entailment does not hold, because
inconceivability might just reflect human's lack of imagination,
and therefore transcendental arguments are in trouble (Mizrahi 2017).
When Mizrahi makes this claim, he uses Kant's Refutation of
Idealism as the prime example, but he intends this point to be applied
to other transcendental arguments too.



However, note that defenders of transcendental arguments have at least
two ways to respond to such a challenge. First, to understand the
transcendental conditionals (i.e., claims asserting that the
possibility of *Y* requires or presupposes *X*) as
(in)conceivability claims is not mandatory. Second, even if we
understand the conditionals this way, there is a weaker version of the
conceivability approach which holds that (in)conceivability is only a
guide to (im)possibility, which is obviously much more defensible than
the stronger version that involves entailment. To be sure, some might
find this version too weak to secure the distinctiveness of certain
arguments being 'transcendental.' If one goes down the
first route, one can opt for other approaches in modal epistemology.
For example, another camp of rationalism in this area is the
*essentialist* approach (Fine 1995; Lowe 2011, 2012, 2013).
According to such an approach, knowledge of the above statement about
metaphysical necessity is based on knowledge of the following:



> 
> It is part of the essence of objective cognition that if there is
> objective cognition, then categories are in place.
> 



Now again, this rendering inherits all the problems with such
approaches, which will not be covered here (see the entry on the
epistemology of modality). One can then reject rationalism in this
area and opt for an entirely different camp, for example the
*counterfactual* approach (Williamson, 2005, 2007, 2016).
According to such an approach, knowledge of the above statement about
metaphysical necessity is based on knowledge of the following:



> 
> If there were objective cognition without there being categories in
> place, then there would be a contradiction.
> 



or



> 
> Objective cognition without categories counterfactually implies a
> contradiction.
> 



This approach invokes certain notion of 'imaginative
simulation' to model the inference, and it is sometimes said
that such an exercise is neither *a priori* nor *a
posteriori*, but 'armchair' (Williamson 2013). Whether
this threefold distinction is reasonable is controversial, as it is
generally thought that armchair inferences are *a priori*
inferences. Now, note that the same dialectic recurs: this rendering
inherits all the problems with such approach, and one might therefore
wish to opt for a different analysis (for more on connecting
transcendental arguments and counterfactuals, see Kannisto 2020).



The point of the above discussion is not to present all the approaches
in modal epistemology; for example, there are other approaches such as
the one that invokes analogical inferences (Roca-Royes 2017). There
are also approaches that might combine several ideas, for example
Husserl's 'imaginative variation' that combines
conceivability and essence (1931/2012). The key message here is that
if transcendental conditionals can be thought to embody claims about
metaphysical modalities, then both considerations from modal
metaphysics and modal epistemology--especially the
latter--will influence what we should say about such
conditionals. Another potential direction is to see whether
metaphysical grounding can be an explanation of transcendental
conditionals (see the entry on metaphysical grounding). Although it
can be tempting and potentially enlightening to connect these
contemporary approaches to the historical tradition, no claim about a
direct historical connection is made here: it should not be
assumed--without textual analyses anyway--that any above
approach captures what Kant, Fichte, and other historical figures had
in mind when they invoked such arguments.


## 6. Transcendental Arguments in Ethics



As we have seen, then, when it comes to transcendental arguments in
epistemology, most of the effort in recent years has been concentrated
at the meta-level, concerning what transcendental arguments are and
what they can be expected to achieve: when it comes to examples of
transcendental arguments themselves, very few new ones have actually
been proposed (for exceptions, see Lockie 2018, Cheng 2022). However,
the picture is different in ethics, where attempts to produce such
arguments are still being made, so that while epistemology perhaps
remains their natural home, the use of transcendental arguments in
ethics is of undoubted significance (see for example Brune, Stern and
Werner (eds.) 2017). Moreover, as with such arguments in epistemology,
when it comes to transcendental claims in ethics, Kant may again be
taken as an important inspiration, especially Kant 1785.



In fact, in view of what was said previously regarding the problems of
transcendental arguments, it is perhaps not really surprising that
ethicists have had fewer qualms in producing them. For, as we saw, the
difficulty when it comes to external world scepticism, other minds
scepticism, and the like, is in finding an argument that will
successfully cross Stroud's 'bridge of necessity',
and establish a conclusion concerning how things are, rather than how
things must appear or how we must believe them to be, and so reach a
conclusion that will satisfy the realist about such matters. However,
in ethics, it is much more acceptable to reject realism, and to adopt
a more anti-realist position of some sort at the outset (cf.
Rahme 2017); as a result, the most that will be called for is a
modest transcendental argument which is not world-directed, as many
ethicists do not want to treat moral values and norms as part of the
'world' anyway, and so see no victory for the sceptic in
failing to establish any more ambitious conclusion, where this may
still be a worry in the epistemological cases.



While until recently there was only a limited discussion of
transcendental arguments in ethics within the 'analytic'
tradition of Anglo-American philosophy (see e.g., Phillips-Griffiths
1957-8; Watt 1975; Harrison 1976; Cooper 1976; Finnis 1977
argues for the value of truth), they have played a significant role in
the social philosophy of thinkers such as Karl-Otto Apel and
Jurgen Habermas (for a broader discussion of transcendental
arguments concerning intersubjectivity in the
'continental' tradition more generally, see Chase &
Reynolds 2011: 89-114 and Russell & Reynolds 2011). Apel has
argued that an ethical perspective is required as a condition for a
commitment to truth, inquiry and successful communication. Habermas
denies this, where instead he thinks that we are committed to
communication and discourse by the pragmatic implications of speech
oriented towards reaching understanding of each other, which for us,
as speaking beings, is unavoidable. Both may be said to be inspired by
C. S. Peirce's insistence on the relation between truth and
consensus, where the search for consensus is said to require as a
necessary condition that we have certain ethical attitudes to others,
such as equal respect and tolerance for their views and commitments.
In this way the suggestion is also made in the practical case, it is
easier for transcendental arguments to take a so-called
'retorsive' rather than a deductive form, aiming to more
modestly show that to make inquiries in this context we simply must
not question certain things to make inquiries in this context (See
Apel 1976b vol II/1980 and 1976a; Habermas 1983. For further
discussion see Benhabib and Dallmayr (eds.) 1995; Illies 2003:
64-92 and Kuhlmann 2017. A comparable form of transcendental
argument is attributed to Emmanuel Levinas in Perpich 2008:
124-149; For a critical discussion of the value of this approach
see Stern 2016).



Moreover, transcendental claims have been given a more prominent role
within recent Anglo-American ethical theory, largely through the work
of Alan Gewirth and Christine Korsgaard. These arguments start not
from claims about truth and communication, but from claims about our
nature as human agents, and what we must then presuppose about the
moral status of ourselves and others. As in epistemology, the promise
of such arguments in ethics has generated much interest and attention.
For illustration, we will discuss a transcendental argument in ethics
proposed by Korsgaard. (For Gewirth, see Gewirth 1981; Beyleveld 1991;
and Illies 2003: 93-128.)



Korsgaard's use of a transcendental argument in fact forms only
part of a wider response to sceptical worries about the demands of
morality ('the normative question'), and is deployed
merely to convince the sceptic that her own humanity has value, from
which a further argument concerning the publicity of reasons is used
to show that she must also then value the humanity of others. The
transcendental argument that Korsgaard proposes is modelled on a
position which she finds in Kant and which she outlines as
follows:



> 
> [Kant] started from the fact that when we make a choice we must regard
> its object as good. His point is the one I have been making--that
> being human we must endorse our impulses before we can act on them. He
> asked what it is that makes these objects good, and, rejecting one
> form of realism, he decided that the goodness was not in the objects
> themselves. Were it not for our desires and inclinations--and for
> the various physiological, psychological, and social conditions which
> gave rise to those desires and inclinations--we would not find
> their objects good. Kant saw that we take things to be important
> because they are important to us--and he concluded that we must
> therefore take ourselves to be important. In this way, the value of
> humanity itself is implicit in every human choice. If complete
> normative scepticism is to be avoided--if there is such a thing
> as a reason for action--then humanity, as the source of all
> reasons and values, must be valued for its own sake. (Korsgaard 1996:
> 122)
> 



This argument can be laid out as follows:



(1) To rationally
choose to do *X*, you must regard doing *X* as
good.
(2) You cannot regard
doing *X* as good in itself, but can only regard doing
*X* as good because it satisfies your needs, desires,
inclinations, etc.
(3) You cannot regard
your desiring or needing to do *X* as making it good unless you
regard yourself as valuable.
(4) Therefore, you must
regard yourself as valuable, if you are to make any rational
choice.


Consider this example. To rationally choose to eat this piece of
chocolate cake, I must think that eating the cake is good in some way.
How can I regard it as good? It seems implausible to say that eating
the cake is good in itself, of intrinsic value. It also seems
implausible to say that it is good just because it satisfies a desire
as such: for even if I was bulimic it might do that, but still not be
regarded as good. A third suggestion, then, is that it can be seen as
good because it is good for me, as satisfying a genuine need or desire
of mine. But if I think this is what makes eating the piece of cake
good, I must value myself, as otherwise I could not hold that
satisfying me is sufficient to make something good enough for it to be
rational for me to choose to do it; so I must regard myself as
valuable. Put conversely: suppose that you thought that you and your
life were utterly worthless, pointless, meaningless--that in your
eyes, you were valueless. And suppose that you are faced with a piece
of cake: on what basis would you choose it eat it? It seems unlikely
that there is something intrinsically good about eating it, or that
you should do so just because you find yourself with a desire to do
so, even while finding your existence valueless. It seems that the
only reason to do so would be if you thought eating the cake brought
you some genuine benefit--but if you thought your life was
worthless, how could you see this as a reason either? Why is bringing
benefit to something that in your eyes is so utterly without value a
reasonable thing to do?



There are some dangers in this argument, however. One, which Korsgaard
considers, is that it might lead to 'self-conceit'
(Korsgaard 1998: 54. Cf. also Korsgaard 1996: 249-50): that is,
I might conclude from this that I am supremely valuable, simply as
myself, which could obviously then get in the way of my ethical
treatment of others. But, this worry might be lessened by the thought
that while the argument gets me to see that I must find something
valuable about me, it need not be anything about me in particular, and
perhaps could instead be something about me that is more
general--such as my humanity or personhood. However, while
Korsgaard says that reflection will indeed lead us in this more
general direction, we will need to see how. A second, perhaps related,
worry is that this argument has a troubling parallel in the case of
Satan, where Satan goes through (1) to (4) above, and concludes that
he must regard his devilish nature as valuable. If this argument
somehow entitles us to regard our own humanity or personhood as
valuable, why doesn't it entitle Satan to think the same about
his nature? This is not the same as self-conceit, because he is not
valuing himself as Satan just *qua* Satan; he is valuing his
nature, just as we are valuing ours. Nor does devilishness seem any
less central to his nature than humanity is to ours. So it is hard to
see how the Satanic parallel can be avoided by the argument as it
stands.



Nonetheless, it is possible that something can be built on the central
idea of the argument, which seems to be this: As long as we think we
can act for reasons based on the value of things, but at the same time
reject any realism about that value applying to things independently
of us, then we must be treated as the source of value and in a way
that makes rational choice possible. We can therefore see
Korsgaard's second argument as attempting something along these
lines, using her notion of practical identity to perhaps avoid the two
problems we have identified with the Kantian argument.



Here, then, is an outline of Korsgaard's second argument:



(1) To rationally
choose to do *X*, you must take it that doing *X* is the
rational thing to do.
(2) Since there is no
reason in itself to do *X*, you can take it that *X* is
the rational thing to do only if you regard your practical identity as
making *X* the rational thing to do.
(3) You cannot regard
your practical identity as making doing *X* the rational thing
to do unless you can see some value in that practical
identity.
(4) You cannot see any
value in any particular practical identity as such, but can regard it
as valuable only because of the contribution it makes to giving you
reasons and values by which to live.
(5) You cannot see
having a practical identity as valuable in this way unless you think
your having a life containing reasons and values is
important.
(6) You cannot regard
it as important that your life contain reasons and values unless you
regard your leading a rationally structured life as
valuable.
(7) You cannot regard
your leading a rationally structured life as valuable unless you value
yourself *qua* rational agent.
(8) Therefore, you must
value yourself *qua* rational agent, if you are to make any
rational choice.


The first step is now familiar: To act is to do or choose something
for a reason that may be conscious or uncomscious. The second step is
based on Korsgaard's idea that we have reasons to act because of
our practical identities (such as one's identity as a father, or
lecturer, or Englishman), not because acts have reasons attached to
them in themselves. Once again, realists might demur, claiming that
some actions are rational things to do, because some things have value
as such: so, perhaps knowledge is valuable in itself, thereby making
it rational to seek it. But let us leave such worries aside and assume
with Korsgaard that nothing is objectively rational for us to do.



The third step asks how a practical identity can make something into a
reason for an agent: how can the fact that I am a father make it
rational for me to buy my daughter this toy? The thought here is that
it can only do so if you see value in that identity. Korsgaard
stresses this when she writes:



> 
> The conception of one's identity in question here is not a
> theoretical one, a view about what as a matter of inescapable
> scientific fact you are. It is better understood as a description
> under which you value yourself, a description under which you find
> your life to be worth living and your actions to be worth undertaking.
> (Korsgaard 1996: 101)
> 



So, being a father, whether contingently or essentially, gives one no
reason to be a caring or devoted father of a sort that would have good
reason to buy a daughter a gift; rather, valuing one's
fatherhood does this.



But (moving on to step (4)), how can I see my particular practical
identity as valuable? Korsgaard's position here is that I cannot
see any value in any particular practical identity as such: for, to do
so would mean being committed to realism, to thinking that being a
father, an Englishman, a university lecturer or whatever matters as
such; or (in a way that is in the end equally realist), it matters
because of the intrinsically valuable things it leads you to do. But,
Korsgaard takes such realist positions to be problematic, and so
thinks this will not do as an answer.



So suppose we allow that no particular practical identity can be seen
to have value in itself; Korsgaard then offers as the only remaining
explanation of its value to the agent that has that identity, that
such identities have the general capacity of enabling the agent to
live a life containing reasons: because I have whatever particular
practical identities I do (father, Englishman, university
lecturer...), I can then find things to be valuable and act
rationally accordingly, in a way that gives me unity as a subject.



But then (step (5)), to think that this makes having some sort of
particular practical identity important, you must think that it
matters that your life have the sort of rational structure that having
such identities provides; but (step (6)), to see that as mattering,
you must see value in your leading a rationally structured life. And
then, finally, to see value in your leading such a life, you must see
your rational nature as valuable, which is to value your humanity.



Does this Korsgaardian argument avoid the pitfalls of the Kantian one
discussed earlier? It seems to avoid the problem of self-conceit,
because it does seem that what you end up valuing is not yourself
simply as such, but yourself *qua* rational agent. And as
presented here, it avoids the problem of the Satanic parallel, because
all it shows is that Satan must value his rational nature, not his
devilishness.



For both these problems to be avoided, however, it is important to run
the argument as outlined above, not as it is sometimes presented by
Korsgaard, which is via the notion of need (cf. Korsgaard 1996: 121
and 125). This would follow the same premises as before for
(1)-(5), and then go as follows:



(6\*)  You cannot regard
it as important that your life contain reasons and values unless you
take your need to lead this sort of life as important.
(7\*) You cannot take
this need to be important unless you take yourself to be
valuable.
(8\*) Therefore, you
must value yourself, if you are to make any rational
choice.


The difficulty with (6\*)-(8\*), we think, is that (8\*) does not
stipulate what it is about yourself that you are required to value, so
that this could be my sheer particularity (self-conceit), or if I am
not in fact human, my non-human nature (Satan). This is because (6\*)
just identifies a need, and says that this need could not be important
unless the agent who has the need were seen to be valuable
somehow--whereas the previous argument narrows value down to
rational agency, and so rules out both self-conceit and
devilishness.



We have therefore reconstructed that part of Korsgaard's
strategy who offers an argument to the effect that you must value
your humanity, as a transcendental argument: it is transcendental as
it claims that valuing humanity is a necessary condition of being an
agent which makes rational choice. It turns out that if it is to be
made plausible in this way, a lot depends on accepting
Korsgaard's arguments against realism; but then, as we have
seen, many have always suspected that some commitment to anti-realism
is required to make a transcendental argument convincing. A further
worry when it comes to external world scepticism, as we discussed
above
 (SS3),
 is that this commitment can appear to make the argument redundant,
because anti-realism appears sufficient as a response to scepticism on
its own. However, in this ethical case, this worry is perhaps less of
a concern, because a sceptic could endorse an anti-realist position in
metaethics, without accepting that they or others have value as a
matter of their normative ethics, so that there is still work left for
the transcendental argument to do. To this extent, therefore, it is
not surprising that Korsgaard's claims have given further
impetus to the debate concerning what transcendental arguments are,
and what they can contribute. (For further discussion of
Korsgaard's position as an interpretation of Kant, see Wood
1999: 125-32 and Timmermann 2006; and for further discussion,
see Skorupski 1998, Skidmore 2002, Enoch 2006, Stern 2011, Stern and
Watts 2019).


## 7. Transcendental Arguments in Philosophy of Psychology and Perception



In addition to ethics, transcendental arguments are also widely use in
other areas of philosophy. There are certain prominent examples in
philosophy of psychology and perception. For the former, one idea is
that the possibility of intentional action requires or presupposes the
subject's sensation-based bodily awareness (O'Shaughnessy
1980, 1989, 1995; Bermudez 1995). This general idea has been
cashed out in different ways. One such instance begins with the fact
that we do perceive and act upon the world, and proceeds with the
inference that the possibility of guiding actions *via* our
perceptions of the world requires or presupposes spatial awareness of
our bodily positions. Although here the starting point concerns
perception in general, it is standard to think of these inferences
from some examples of vision: our visual experiences of worldly
objects enable us to act upon those objects only if the subjects are
capable of mapping the information that they give about the spatial
relations between our bodies and the objects in question. Another
instance begins with the fact that we do experiences ourselves as
performing bodily-directed intentional actions. This can be motivated
by considering simple examples such as scratching one's head. To
do this, it is not enough to locate the spot on one's head where
one wishes to scratch. It is also needed to be able to locate that
spot relative to the rest of one's body. That is, the
possibility of the above experiences requires or presupposes certain
kind of representational awareness of one's body. Some might
even go further to hold that one needs to be aware of that spot as
part of one's body. Why is this so? The idea is that one
normally scratches the spot with one's hand, and in moving the
hand to the location of the spot, it seems necessary to holistically
represent one's body, otherwise one would not be able to direct
one's hand to the spot smoothly.



One distinctive feature of these arguments is that they seem to make
empirical claims about the world, so the status of such arguments can
become a matter of dispute. It is often thought that transcendental
arguments, or at least the conditionals involved, have to be *a
priori* (Bermudez 1995; Schwenkler 2012), but if they can
be tested through cases in real life, specifically clinical cases from
neuropsychology, it is then become unclear whether such conditionals
are indeed *a priori*. Ian Waterman's case might be the
most discussed one in this context. He unfortunately lost all
functions on the large myelinated sensory fibers below the neck, and
as a result he almost had no sensation below the neck (Cole 1991). At
the beginning of such a condition, he could barely move without
falling on the ground, but after appropriate training, he became able
to retrieve some capacities for walking and other actions through the
help of sight. Now why is this relevant? Recall that the first
transcendental conditional introduced in this section has it that the
possibility of guiding actions *via* our perceptions of the
world requires or presupposes spatial awareness of our bodily
positions. After training, Waterman could guide his actions
*via* his visual experiences of the environment, but this does
not seem to require or presuppose the relevant kind of spatial
awareness of our bodily positions. If so, then the conditional is
falsified. As for the second transcendental conditional above, it
states that the possibility of experiencing ourselves as performing
body-directed intentional actions requires or presupposes certain kind
of representational awareness of one's body. Now the partly
recovered Waterman could experience himself as performing
body-directed intentional actions, but this does not seem to require
or presuppose the relevant kind of representational awareness of
one's body, since he is now relying on his sight, not his body
image or schema. In this way, cases from neuropsychology might bear on
transcendental conditionals.



But doesn't this make the relevant conditionals *a
posteriori*? After all, they can be falsified by empirical facts
in the actual world. For those who insist that such conditionals are
*a priori*, they might argue that since those conditionals are
*a priori* necessary truths, they are true of all possible
worlds, including the actual world; no wonder empirical cases in the
actual world can be relevant. This involves very complicated issues:
true logical and mathematical statements are supposed to be true of
all possible worlds, including the actual world, but they cannot be
refuted by empirical cases in the actual world. This links back to
considerations about modal metaphysics (see SS5 above), and about
philosophy of language and epistemology too. Note that this issue is
connected to another important issue concerning naturalisation
(Bermudez 1995): to bring transcendental conditionals to bear
on actual cases is supposed to be a virtue, because it fits the
current *Zeitgeist*, but given the empirical bearings, how can
such conditionals be *a priori*? It is not clear that the
literature has engaged with this issue sufficiently. In a way, *a
priori* statements bear on the empirical world: e.g., 'any
sister is a sibling' bears on all sisters; however, this *a
priori* statement cannot be refuted by empirical investigations of
these individuals in the empirical world.



Philosophy of perception is another area that is filled with
transcendental arguments, even though the users sometimes do not label
them as such. For example, consider the view that the possibility of
intentionality requires or presupposes that perceptual experiences
have representational contents (McDowell 2008, against Travis, 2004,
2018; the 'content view' as it is sometimes called). The
sub-arguments for such conditionals can be very complicated. It might
rely on the idea that rational relations must be between contentful
episodes, otherwise one might commit the notorious 'myth of the
given' (Sellars 1956). Such pictures can demand an even stronger
conditional, that the possibility of intentionality requires or
presupposes that perceptual experiences' representational
contents are all conceptual (McDowell 1996). Relatedly, it is also
proposed that the possibility of intentionality requires or
presupposes the 'disjunctive conception of perceptual
evidence' (McDowell 1982, 1995, 2008). If the force of
transcendental arguments is in doubt, then many arguments in
philosophy of perception would be problematic. (For more on McDowell,
see Cheng 2021b). To be sure, there can always be disagreements about
whether these arguments are transcendental at all. To settle this, one
needs to check whether these arguments fit the six characteristics
listed in section 2. However, one difficulty is that it is unclear
whether we should take them as individually necessary and jointly
sufficient. Another difficulty is that other practitioners would
presumably disagree with some of the characteristics listed above.
Here we regard the above examples as transcendental arguments
primarily because they fit the schema offered at the beginning of this
entry, but the relations between these arguments and the
characteristics listed in section 2 are of course complicated and
controversial.



In addition to the above examples, there are some notable recent
developments in this area. One prominent theory in this area is
naive realism, the view that the phenomenal characters of
perceptual experiences are partially constituted by their objects
(Campbell 2002; Martin 2006). As such, it is not obviously
transcendental in any sense. However, there is a recent twist that
builds the transcendental element into the theory: according to this
new version, naive realism is an integral part of the
transcendental project of explaining *how it is possible* that
perceptual experiences have the distinctive characters that they do.
That is, naive realism is not only the best explanation of the
relevant phenomenal characters; it is *the only viable*
explanation for why certain perceptual experiences have the kind of
phenomenal characters they do (Allen 2017, 2020). Another recent
example concerns the relation between perceptual experiences and
imaginative reflection on the phenomenal characters of such
experiences (Gomes 2017): more specifically, imaginative
reflection 'draws on the knowledge we possess of the
phenomenal character of our perceptual experience and exploits various
of our imaginative and reflective capacities to provide us with
support for modal claims about whether certain non-actual types of
perceptual experience could support various forms of thought'
(p. 140). In this context, it is crucial to emphasise that
transcendental arguments can at best reveal properties that perceptual
experiences *must* have, or *must* lack, given the modal
force of such arguments. For example, one might think that visual
experiences must have a field-like structure, as visual objects need
to be placed within an overarching space. This specific claim, to be
sure, has proven to be highly contested (Campbell 2007; Schwenkler
2012; French 2018; Cheng 2019).


## 8. Concluding Remarks



We have looked in some depth at the role of transcendental arguments
that have been given in philosophy, not only in refuting the
epistemological sceptic, but also in ethics, philosophy of psychology,
and philosophy of perception. As we have seen, such arguments clearly
face challenges, both in their details but also at a more general
level, concerning how much they can ever hope to achieve. However,
while these challenges are certainly significant, it would be wrong to
exaggerate them: for, as we have also seen, the range of potential
uses for such arguments is wide, while it seems that their intriguing
power, as well as their alluring promise, will mean that philosophers
will continue to be drawn to them. As a result, therefore, it seems
unlikely that those engaged in the subject will ever cease to feel
that 'tenderness for transcendental arguments' (Strawson
1985: 21) instilled in them by Kant and others.