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reconciling wide content with individualism, consider (2) and especially
(3) in light of the constitutivity and suf¬ciency theses and my argument
thus far. In effect, (3) says that if you take realizers that satisfy the con-
stitutivity thesis and ¬x their context you have realizations of intentional
states with the same content. Yet, as the conjunction here makes clear,
the realizers that satisfy the constitutivity thesis themselves satisfy the suf-
¬ciency thesis with respect to intentional states only in conjunction with
their context. Thus, we lack any one realizer that satis¬es both theses.
This is precisely the problem that we identi¬ed with Horgan™s regional
supervenience thesis considered as an attempt to develop the standard
view of realization in a way that accounts for the context sensitivity of
mental states.
Furthermore, since Walsh™s view invokes a relatively unconstrained
notion of context, it would seem subject to a variation on the single neu-
ron objection that I introduced in section 5. Walsh says that he thinks
of a context “as corresponding to a set of properties of an individual™s
environment.” If we make the context rich enough “ including, for ex-
ample, properties that might normally be determined by an individual™s
internal, functional organization “ then two identical single neurons
that realize the same physiological state (and so satisfy the constitutivity
thesis) could also realize the same psychological state relative to that con-
text. But this does not so much provide us with a realization that also
satis¬es the suf¬ciency thesis as indicate a problem with drawing on such
Individualism and Externalism in Cognitive Sciences
136

a notion of context as a way of saving the standard, entity-bounded view
of realization.11
Walsh™s defense of the view that he calls alternative individualism is also
an attempt to build context sensitivity into individualistic views in the
metaphysics of mind and science. At the heart of alternative individualism
is a context-sensitive version of the local supervenience thesis “ that causal
powers supervene on the intrinsic, physical properties of individuals “ that
serves as a premise in the argument from causal powers that we discussed
in Chapter 4. Walsh takes alternative individualism to preserve what is
right in that argument. The supervenience thesis that Walsh defends
claims that for all contexts, necessarily an object™s having a given context-
sensitive, intrinsic property in a context ¬xes the psychological properties
it has in that context. We can express this succinctly in symbols, where
¦
“γ” denotes a context,“¦” an intrinsic, qualitative property, and “ ” the
psychological kinds that an individual, x, instantiates:
∀γ· ∀x(¦ x, γ ⊃
¦ x, γ).
Walsh™s claim here generalizes beyond psychology to scienti¬c taxonomy
in general.12
The problem with this supervenience thesis, as with that of the ortho-
dox individualist (which simply drops the contextual relativization) is that
there is a wide range of examples for which it simply does not hold. Two
organisms that were intrinsically identical in the very same context could
belong to different species because of ancestral, phylogenetic differences
between them; two viral infections in a person “ and thus, I assume, in one
context “ that give rise to identical symptoms and are treated by the same
regimen can be of different types because they are caused by different
viral agents. In both cases, the identity of consequences in a given context
(or even of intrinsic, qualitative properties) does not determine sameness
of scienti¬c kind because the corresponding kinds are individuated, in
part, by causal antecedents, not causal consequences.
Recall that my basic criticism of the original argument from causal
powers was that it equivocates on “causal powers,” invoking a wider no-
tion in one premise (individuation in science is by causal powers) and
a narrower notion in another (causal powers supervene on an individ-
ual™s intrinsic properties). Alternative individualism is an attempt to sal-
vage both of these premises, but it too involves much the same equiv-
ocation, this time on context-sensitive causal powers. The fundamental
problem in all of these cases is brought out once one asks whether rela-
tional properties are, or are ¬xed by, such powers: They must be if the
Context-Sensitive Realizations 137

premise about scienti¬c individuation is to be true, but they can™t be if the
premise about supervenience is to be true. Alternative individualism, like
Walsh™s wide content individualism, is committed to causal powers (within
a context) subsuming relational properties “ that is what allows these
modi¬cations of individualism to be seemingly compatible with external-
ism about the mind “ but this is precisely what calls into question whether
such powers are a subset of (or supervene on) an individual™s intrinsic
properties.
Considered in tandem, Horgan™s and Walsh™s views illustrate that the
basic tension in the standard view of realization between the constitutivity
and suf¬ciency theses is not easily relieved. Placing emphasis on the need
to move beyond the boundary of the individual subject in order to have a
determinative base for mental states, as Horgan™s regional supervenience
does, highlights the point that realizations satisfying the suf¬ciency thesis
do not themselves satisfy the constitutivity thesis. And emphasizing that
realizations that satisfy the constitutivity thesis determine mental states
only given a shared context, as Walsh™s (2) does, suggests, conversely, that
in at least some cases realizations that satisfy the constitutivity thesis do
not satisfy the suf¬ciency thesis.
Those willing to hum along to the tune of the context-sensitive view of
realization and entertain the idea that properties at least sometimes have
wide realizations might reasonably wonder whether the context-sensitive
view has more radical implications for how we think about the mind. I
want to take up one such putative implication in each of the next three
sections, beginning in each case with a question.13


7 keeping realism a¬‚oat
Why doesn™t the context-sensitive view lead to an irrealist position on
mental states? Consider the very idea of a physical state™s being “meta-
physically suf¬cient” for a given mental state. We have seen that, strictly
speaking, metaphysical suf¬ciency requires both that some physical sys-
tem be in a certain state (a total realization) and that certain background
conditions hold, thus making even total realizations metaphysically con-
text sensitive. This view of total realizations underwrites the realism about
mental properties that I invoked at the end of section 5, a realism that
would be called into question if it could be shown that total realizations
are also epistemically context sensitive, as core realizations are.
In fact, we might well think that total realizations must be epistemically
context sensitive if the core realizations they contain as proper parts are.
Individualism and Externalism in Cognitive Sciences
138

A suf¬cient condition for an individual having a given mental state is that
there be a total realization of that state whose core part lies wholly or in
large part in that individual. But if that core realization is epistemically
context sensitive, then so too is that state itself, and mental states start to
sound more like merely ascribed states of individuals.
Moreover, it seems doubtful that there is any particular physical state
that is “the” total realization for a given property, for what we pick out as a
total realization will depend on what we count as part of the correspond-
ing system and what counts as background conditions to it. Once one
“goes wide” about realization, as perhaps one should, we have a plurality
of ways of thinking about the underlying metaphysics, a pluralism that
suggests that we, rather than the world, are the source for how the distinc-
tions between individual, system, and background conditions are drawn.
Thus, the context-sensitive view is faced with much the problem that we
posed for the modi¬ed standard view in section 5, and an externalist
metaphysics pushes us toward irrealism about mental states.
Reply: This irrealist challenge can be arrested. In the ¬rst place, epis-
temic context sensitivity is not simply inherited by total realizations from
their constituent core realizations. A total realization of P could have
been de¬ned simply as a state of S that is metaphysically suf¬cient for
P, that is, by dropping the relative clause that refers to core realizations,
without signi¬cantly changing the view that I have defended. There can
be multiple total realizations not because there are multiple core real-
izations that are epistemically context sensitive, but because, given the
complexity of the sort of systems there are, there will at least typically be
many ways in which those systems can be arranged or instantiated, each
of which will metaphysically suf¬ce for P.
Consider pain. The nociceptive system that realizes pain is compli-
cated, and there are many states it can be in that would metaphysically suf-
¬ce for an individual organism to be in pain. Even given a particular core
realization of pain “ say, as a particular instance of C-¬ber stimulation “
there remain multiple total realizations for that core realization be-
cause there are various noncore parts of the realization that could
suf¬ce for the mental state of pain, even though just one of these will, in
any given instance, form part of the total realization in that case.
As with the boundary of individuals, the line between what falls within
any given system (and so can be part of the total realization for any
properties it realizes) and the background conditions for its existence
and operation can be fuzzy. The individuation conditions for systems are
likely to be more coarse grained than for individuals, but in both cases
Context-Sensitive Realizations 139

these are highly constrained by the physical facts. It is not simply up to us
to determine what constitutes a system or the system of relevance. Like
the individuals that they either constitute (in cases of entity-bounded re-
alization) or that constitute them (in cases of wide realization), systems
have individuation conditions, and these depend only in minor ways on
our epistemic proclivities and fancies. Whether teeth or saliva form part
of the digestive system, or operate as background conditions for its op-
eration, may be “up to us.” But the facts about how food is broken down
into energy and distributed within the body, and how waste products are
formed and removed from the body determine what, plus or minus a
bit, constitutes the digestive system. We discover, rather than invent, what
physically constitutes the digestive system; the same is true of cognitive
systems, whether they be entity bounded or wide.
Cases in which there are genuinely alternative systems which we could,
plausibly, identify as the locus of a given total realization are likely to
be rare. Again, focus on the physiological systems that are a paradigm
here. While it is logically and metaphysically possible that there be two or
more candidate systems for the realization of any biological function “
respiration, circulation, digestion, reproduction “ the requisite complex-
ity to each of these systems in practice makes it relatively unproblematic
to single out what “the” relevant system is for any given property. The
same is true of cognitive systems. As with any systematic theorizing, in sci-
ence or elsewhere, this theorizing about both entity-bounded and wide
cognitive systems is subject to error, modi¬cation, and revision, but this
is not the sort of epistemic context sensitivity that would undermine a
realist view of the ascription of psychological states.


8 pluralism about realization
Why don™t all mental states have wide realizations? Suppose that we accept
the view that at least some mental states have wide realizations. Might we
replace the existential by the universal quanti¬er here, and suggest that
the moral of the story so far is that mental states have individualistic core
realizations but wide total realizations?
Reply: Given that social actions appear to have radically wide realiza-
tions, and the ways in which at least our common-sense conception of
the mind is linked to such actions via the idea of a reason for acting, we
might have pause about the latter of these two views. Here I want to make
some brief comments about the former claim, the idea that all mental
states might have wide realizations.
Individualism and Externalism in Cognitive Sciences
140

One natural thought in response to the claim that all mental states have
wide realizations is that mental properties typically denoted by monadic
predicates “ such as pain “ surely have entity-bounded realizations, since
their presence at a time or over a time interval is determined solely by
what is going on within the boundary of the individual who has the prop-
erty. In fact, given that the nociceptive system is a proper part of an
individual organism, as I suggested earlier, this conclusion about pain
seems inescapable. More generally, there would seem to be a range of
mental states and processes that form part of entity-bounded systems:
Good candidates include fear, motor imagery, and haptic perception.14
It has been the working assumption of much traditional cognitive sci-
ence, committed as it has been to individualism about the mind, that all
mental states and processes can be viewed in such a way, with the task
of cognitive science being to uncover what these entity-bounded systems
are. While I think that there is little reason to think that such a general
view of cognition can be sustained, my point here is that the individu-
alistic view of at least some cognitive processes does seem correct. This
suggests a general conclusion “ that whereas some of our mental states
have an entity-bounded realization, others have a wide realization.
It may be worth brie¬‚y pondering the more radical alternative that I
am somewhat casually rejecting here, that no psychological states actu-
ally have entity-bounded realizations. This would imply that the cognitive
sciences are radically mistaken, and supposing that many noncognitive,
biological systems are individualistic, suggests that there is a radical junc-
ture between the cognitive and the biological. The scale and nature of
the error within the cognitive sciences would be akin to that which be-
haviorists charged introspectionists with in the ¬rst part of the twentieth
century: There simply aren™t the kinds of internal states (systems) that
such a psychology seeks. While I don™t say that it is impossible that the
cognitive sciences have gone awry so radically, it does seem that one
would want very strong reasons for thinking that the smallist metaphysics
on which they have relied is completely mistaken. It seems to me clear
where the burden of proof lies on this issue.
If some of our mental states do have entity-bounded realizations, while
others have wide realizations, then there is a respect in which the standard
way of characterizing (total) realizations via the Ramsey-Lewis method
for de¬ning theoretical terms “ a method commonly used to charac-
terize functionalist views in the philosophy of mind “ is both restricted
and misleading. Ramsey-Lewis sentences purport to represent complete
Context-Sensitive Realizations 141

theories for a given domain and are constructed by conjoining all of the
truths speci¬ed by such theories; one derives the total realization for a
particular property or state by conjoining its core realization to the re-
alization of complete theories for the domain. Here let us simply grant
that such a conception of folk and scienti¬c theories is coherent and
a close enough approximation of the theories we have actually devel-
oped to model those theories usefully. Now, if some part of psychology
is wide, then since the total realization for a complete psychology will be
a wide realization, that for any particular psychological state will also be
wide. Given the wide nature of the propositional attitudes and at least
some subpersonal psychological states, the goal of characterizing a com-
plete psychology implies that the total realizations of any psychological
state must be wide.15
If we follow Brute Intuition and our brief re¬‚ection on cognitive sci-
ence, and insist that surely some psychological properties have entity-
bounded realizations, and thus accept my claim that not all psychological
properties are wide, the Ramsey-Lewis method appears to provide us with
no way to represent a signi¬cant distinction. The most obvious modi¬ca-
tion to the standard Ramsey-Lewis view “ to attempt to de¬ne properties
like being in pain by reference to a theory of pain, and properties like
believing that p by a theory of belief “ fails, because each of these theo-
ries will almost certainly mention terms from the other, and so will not
allow one to de¬ne properties with entity-bounded realizations. I leave
further exploration here to those more enamored with the Ramsey-Lewis
method than am I.


9 abandoning the subject?
Why aren™t subjects or bearers of mental states themselves wide? The char-
acterization of wide realizations preserves the idea that properties with
such realizations are still properties of individual subjects. Thus, ¬tness
remains a property of individual organisms even though its realization is

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