Reasons are causes, but that's where the philosophical work begins.
I assume that there are mental events, and that they typically have effects.
Indeed, mental events often cause nonmental events, like bodily motions. If
a person raised her arm because she noticed a friend, and wanted to
attract the friend's attention, the arm-rising had a mental cause. If someone
decides to turn on the stereo, and so pushes a certain button with her right
hand, the motion of her hand was caused by a mental event. But whenever
we humans move our limbs, our bodily motions are caused by certain
muscle contractions, which in turn have various biochemical causes. So
there is pressure to say that mental events are biochemical events, even if
we cannot say much about the details. For how could a single effect, like
the rising of an arm, have both its biochemical causes and distinct mental
causes? I think we can answer this rhetorical question, which exerts a
strong grip on contemporary philosophy of mind, without lapsing into an
objectionable form of dualism.
1.
Here's the idea: when a person moves their body for a reason, the bodily
motion is caused by an action, which in turn has a mental cause; actions are
themselves mental events; and our concept of causation is such that there
is no insoluble overdetermination problem if a bodily motion B is caused by
a (mental) action that is distinct from any biochemical cause of B. For
example, when a person intentionally raises her arm, her action is an event
of trying to raise her arm. This mental event causes the rising of her arm.
And this can be so, even if the action/trying is distinct from any biochemical
cause of the arm-rising, because we have a concept of causation such that:
an event C is a cause of event E if the occurrence of C explains-in
accordance with a ceteris paribus law--the occurrence of E; and an
arm-rising is suitably explained by the occurrence of an action, whether or
not the action is a biochemical event, if the arm in question rose because
the person in question raised her arm. A closely related semantic point is
that 'x raised her arm' is true iff x was the agent of a process that began
with some action by x and ended with a rising of her arm.
So if a person raised her arm because she noticed a friend, the causal
sequence is as follows: the onslaught of some belief (about the friend), then
the action/trying, then the arm-rising. The occurence of the first event
explains the occurrence of the second, which explains the occurrence of the
third; and this can be so, even if the first and second events are distinct
from any biochemical causes of the third. This makes room for a kind of
event dualism that allows for the causal closure of the nonmental, and the
supervenience of the mental on the nonmental. Or so I claim--and try to
argue--in Causing Actions. Here, I'll stick mainly to exposition of the claims.
But let me also say a little by way of motivating the project.
In my view, Descartes was basically right about the specialness of persons,
their thoughts, and their (free) actions; he (and Kant) just had the wrong
metaphysics. In "Mental Events," Davidson tried to reconcile autonomy and
causation via his version of token physicalism. While I find this proposal
attractive, I just don't believe it's true--and not for lack of trying. Perhaps
every mental event really is a physical event, in some nontrivializing sense
of' 'physical'. But I don't see any evidence for this strong claim; and the
various "what else" or metaphysical arguments evaporate given a little
imagination. Causing Actions is, primarily, an attempt to provide a
non-Cartesian alternative to token physicalism. I assume that if token
physicalism is true, every human mental event is a biochemical event; and
talk of non-human mental events, if such there be, just complicates matters.
So my focus is on saying how one can avoid both Cartesian dualism and the
"naturalistic" thesis that each human mental event is a biochemical event.
Whether one wants to avoid this thesis will depend, in part, on how one
reacts to another rhetorical question: how could any biochemical event have
all the properties of a mental event?
I suspect that this question is unanswerable. But even if you don't share this
suspicion, even a little, you might want to know if some non-Cartesian form
of dualism is tenable. For if so, the fact that our mental events often have
bodily effects doesn't show that our mental events are biochemical. If I'm
right, one shouldn't reason as follows: mental events are person-internal
events that often cause bodily motions; and we have discovered, by doing
science, that the person-internal causes of bodily motions are biochemical;
so mental events--or at least those with bodily effects-are biochemical. I
grant the first premise but not the second. If we can make sense of the idea
that mental events are causes distinct from any biochemical events, then
we haven't (yet) discovered that the person-internal causes of bodily
motions are biochemical requires. Sellars spoke of us having "manifest" and
"scientific" images of ourselves and our place in the world. In the manifest
image, people act for reasons; in the scientific image, members of a certain
species exhibit various behaviors caused by intricately structured brains. My
hunch is that the (rationalizing) causes visible in the manifest image are not
locatable in the (impersonal) scientific image. This is a familiar thought: our
best scientific accounts of the world and our place in it will not make
reference to reasons or people who do things for reasons; at least not if
'scientific' has any real bite--suggesting the kind of theoretical structure and
unity exhibited by our best current theories in physics, chemistry, and
biology. And while my mental events are located inside my body, it doesn't
follow that you can open my head and witness my mental events; though
perhaps you can see me raise my arm, even if the action that causes the
arm-rising occurs beneath my skin, much as you can see a plant whose
roots lie beneath the surface.
In the book, I sketch some reasons for taking this possibility seriously. But
it's hard to even debate the issue with specters of eliminativism and
Cartesian dualism still haunting. Those who follow Sellars in taking science
to be "the measure of all things" will endorse the following conditional: if the
familiar hunch is correct, there are no mental events. (Debate will then
ensue about whether modus ponens or modus tollens is the correct
response.) But I think the hunch itself is more plausible than the conditional;
though I also think the conditional is more plausible than eliminativism, which
may well be maximally implausible. Still, it's not enough to just declare that
there are mental events, whether or not any identity thesis is correct. We
need to see how there could be causes that somehow lie outside the scope
of natural science. And the answer isn't that people are Cartesian souls (or
transcendental egos) whose reasons lie "outside" of ordinary spacetime:
even if this is comprehensible, it makes a mess of the idea that reasons are
often causes of events that occur "within" ordinary spacetime. The question
is whether any plausible alternative answer is available.
2.
In trying to provide one, I cover a lot of terrain: the semantics of action
sentences and 'that'-clauses; the nature of actions and propositions; the
relation between events and facts; our concepts of causation and
explanation; ceteris paribus laws; the essentially corporeal nature of
persons; and why the mental supervenes on the physical. But this way of
listing the topics may already suggest how they might be connected. And
like Sellars, I think philosophers are in the business of saying how things
"hang together."
In the introduction, I say a little about why the distinction(s) between identity
and constitution don't matter much with respect to the "how is it possible"
questions that interest me. However you describe the situation, there is
work to do: either we show how it's possible for certain biochemical events
to have all the properties that our mental events have; or we show how it's
possible for bodily motions to have mental causes and distinct biochemical
causes.
The first step in pursuing the latter strategy is to get clear about what is
involved in paradigm cases of mental causation: cases in which a person
does something for a reason. For a philosopher in the analytic tradition, this
is an invitation to think about the meaning of action sentences. I argue that
the logical form of a sentence like (1) involves quantification over events as
in (1L), which is an elaborated variant on Davidson's semantics for action
sentences (using '#' for an existential quantifier):
(1) Nora raised her arm
(1L) #e{Agent(e, Nora) & #f[Ends-in(e, f) & Rise(f)] & Theme(e, her arm)};
where 'Ends-In' expresses a whole-to-part relation beween (i) an
"accordion-style" event e, whose first part is an action by the Agent (i.e.,
the doer) that causes subsequent parts of e, and (ii) an event f involving
some change in the Theme (i.e., the object saliently affected object at the
end of the process). On this view, (1) is true iff Nora performed an action
that started a process that ended with a rising of her arm. In defending this
proposal, I draw on the work of many theorists: Hornsby, O'Shaughnessy,
Parsons, Thomson, etc. It's a familiar point that Nora's arm rose if (1) is
true, and (1) is true if Nora raised her arm at noon. In my view, (1L) delivers
the best explanation such entailments, and the gloss of (1L)-in terms of a
process with an action and an arm-rising as (causally related) parts-delivers
the best overall account of how actions are related to action sentences. (In
forthcoming work, Events and Semantic Architecture, I'll discuss the issues
about logical form in much greater detail.) Some philosophers are inclined to
dismiss the idea that actions are internal causes of bodily motions. But
there is much to be said in favor of this old idea, and little to be said against
it, once it is detached from the mistaken claim that every action is caused
by some act of willing.
Chapter two offers a Fregean semantics of 'that'-clauses: 'that P' is a
device for referring (in a given context) to the Fregean sense of 'P' (in that
context); so the phrases 'that Fido barked' and 'that Rex barked' can have
different referents, even if Fido is Rex. But this result is achieved without
abandoning semantic innocence. Even in 'that Fido barked' and 'that Rex
barked', 'Fido' and 'Rex' have their customary referents; so pace Frege, if
the dog Fido is the dog Rex, both names (always) refer to the same dog. In
my view, the complementizer 'that' plays a significant semantic role; it
serves as a kind of indexical that picks out the sense of the sentence it
introduces. I show how this can account for the standard range of facts
(involving Paderewski, Mates-sentences, etc.), and how it lets us apply to
'that'-clauses the independently motivated distinction between
compositionality and substitutivity.
The main interest (for these purposes) of the neo-Fregean semantics is that
lets us distinguish the fact that Fido barked from the fact that Rex barked,
while granting that the embedded sentences 'Fido barked' and 'Rex barked'
have the same "truth-maker"--viz., the event of Fido/Rex barking. Let a
singular event thought be the Fregean sense of a sentence that is true
(according to a correct eventish semantics) iff an event of a certain sort
occurs, where (as a matter of a fact) exactly one event of that sort has
occurred. For example, the sense of 'Socrates died' is a singular event
thought. In chapter three, I use this notion to capture a familiar and
attractive idea: we have a concept of explanation that is a concept of an
intentional relation between facts, and an intimately related concept of
causation that is a concept of an extensional relation between events.
Indeed, I think we have concepts of explanation and causation such that:
the latter is a concept of the transitive closure of the extensionalization of
the intransitive intentional relation that the former concept is a concept of.
Where singular event thoughts are concerned: if the fact that P explains the
fact that Q, then the event e that verifies 'P' is a cause of the event f that
verifies 'Q'; and if the fact that Q explains the fact that S, then the event g
that verifies 'Q' is a cause of the event h that verifies 'S'; and if f = g--that is,
if 'Q' and 'R' are verified by the same event-then e is a cause of h. For
example, if the fact that Garfield howled (at time t) explains why Fido
barked (at t*) , then the event of Garfield's howling caused the event of
Fido's barking. And if the fact that Rex barked (at t*) explains why the
neighbor complained, then the event of Rex's barking caused the complaint.
And since the event of Fido's barking was the event of Rex's barking, the
event of Garfield's howling caused (without explaining) the neighbor's
complaint. Of course, this conceptual connection between causation and
explanation goes both ways: if the event that verifies 'P' is not a cause of
the event that verifies 'Q', then (the singular event thought) that P does not
explain (the singular event thought) that Q. To get an interesting sufficient
condition for causation, which is what we need if we want to explain how a
bodily motion can have a mental cause, we need an interesting sufficient
condition for explanation.
I suggest a version of the traditional covering-law idea. A singular event
thought 1 explains another singular event thought 2 if: 1 and 2 are
(respectively) the senses of the antecedent and consequent of a ceteris
paribus law; the events that verify 1 and 2 instantiate the law; and the
instantiation is "normal" in a sense that flows from the proposed account of
ceteris paribus laws. To a first approximation, if it's a ceteris paribus law
that the temperature of a gas rises when its pressure rises (holding volume
constant), then: if the pressure rises and the temperature goes up, the
former is a cause of the latter. But there are lots of ancillary issues to deal
with, from the alleged vacuity of ceteris paribus laws to the asymmetry of
explanation. The burden of chapter four is to show that: ceteris paribus
laws are just fine; and if you stick to singular event thoughts covered by
ceteris paribus laws, the covering-law model is just fine as a sufficient
condition for explanation. The details initially appear to be quite removed
from the philosophy of mind; but such is life. Indeed, part of the suggestion
in Causing Actions is that much of the work needed for an adequate
philosophy of mind lies in getting straight about our concepts of causation
and explanation; so in thinking about thought, we are led to think about
(inter alia) the semantics of causative verbs and the relation of shadows to
flagpoles.
In chapter five, however, the focus is squarely on traditional questions about
persons and their mental properties. The aim here is to sketch and motivate
the promised alternative to token physicalism, deferring until chapters six
and seven the needed replies to objections. After some initial discussion of
Descartes, and why his (disastrous) picture of mental causation is
seperable from his (much better) intuitions about thinkers, I suggest
replacing the picture of mental causation indicated in (2) with the picture
indicated in (3):
(2) S --> BE --> ... --> BE --> ME --> ... --> ME --> BE --> ... --> BE --> R
/ --> ME --> ... --> ME --> \
(3) S R
\ --> BE --> ... --> BE --> /
where arrows indicate causal relations; 'S' and 'R' stand for an
environmental stimulus and behavioral response; 'BE' and 'ME' indicate
biochemical and mental events.
According to (2), mental events lie "causally between" certain biochemical
effects of the stimulus and other biochemical effects of the response.
Descartes adds the claim that mental causes are different in kind from other
causes. But token physicalists can adopt the picture, shorn of this claim, by
saying that the mental events are biochemical events as shown in (2*):
(2*) S --> BE --> ... --> BE --> BE/ME --> ... --> BE/ME --> BE --> ... -->
BE --> R
where the dual designation 'BE/ME' encodes the idea that some
biochemical events have the properties of mental events-and thus differ
from mere biochemical events.
According to (3), rationalizing causes do not intrude into biochemical causal
chains--or threaten the causal closure of the physical; but neither are mental
events a species of biochemical events. Rather, the rationalizing causes of
a bodily response-say, the motion of Nora's arm-are ontologically distinct
from any biochemical casues of the response. And if Nora raised her arm
intentionally, then the last mental event in the "upper" causal chain will be an
action: Nora's trying (successfully, as it turned out) to raise her arm. Why
are we entitled to say that the action causes the bodily motion? The answer
is long and requires chapter seven. But let e1 be the event of Nora's trying
to raise her arm, and let e2 be the event of her arm rising. Then the core
idea is that <e1, e2> instantiates a (psychophysical) ceteris paribus law,
and the proposed sufficient condition for causation applies. I argue that this
picture is fully compatible with Strawson's view that our concept of a person
is a concept of something that is (pace Descartes) essentially corporeal.
Chapter five also offers some arguments, developing work by Hornsby, for
distinguishing actions/tryings from any biochemical events. But the initial
point of these is not so much to convince as to flesh out the kind of
non-Cartesian event dualism on offer. Once the position is clearly available,
one can revisit the arguments.
An obvious worry is that bodily motions would be objectionably
overdetermined if (3) were the right picture of mental causation. But I don't
think one can criticize this picture simply by pointing to counterfactual
intuitions (about what would have happened if the biochemical causes of the
arm motion hadn't occurred), or analogies about pairs of assassins sent to
kill the same person, or any of the usual stuff that is supposed to make (3)
look like a nonstarter. The context-sensitivity of counterfactual claims, and
disanologies between events and people, provide ample resources for
keeping quick objections to (3) at bay. The first part of chapter six works
out some details. The more serious issue is whether event dualists can
allow that the mental supervenes on the nonmental. If so, the
overdetermination problems go away; if not, the proposal threatens to be
(disastrously) Cartesian after all.
So the bulk of chapter six is devoted to saying how you can have your cake
and eat it: yes, the mental supervenes on the nonmental; and yes, the
mental supervenes on that which can be described from within the scientific
image; but no, mental events can't be identified with biochemical events (or
any events describable from within the scientific image). Persons and their
mental properties are, in an important sense, primitive; nonetheless, they
are also supervenient--and not ontologically basic. It's not obvious that this
view is sustainable. But I think it is a view we have of ourselves and our
place in the world. And an independently plausible (if somewhat
deflationary) conception of supervenience can help us sustain this view.
Here's the idea: global supervenience--the thesis that possible world w1
differs from possible world w2 only if w1 differs physically from w2--is best
seen as a thesis about the individuation of possible worlds; it's not a modal
thesis (about how all properties depend on physical properties) that calls for
explanation (by showing how all properties depend on physical properties).
If w1 does not differ physically from w2, then w1 is w2; and if w1 = w2,
then it's hardly surprising that w1 is like w2 in all nonphysical respects. By
analogy, suppose someone wanted to know why the following
generalization is (necessarily) true: set S1 differs from set S2 only if S1
differs in membership from S2. We can reply that this is how we count sets;
if S1 has the same members as S2, S1 = S2. Possible worlds aren't sets;
but global supervenience may well be a reflection of how we (ought to)
count possible worlds. Following Kripke, I take possible worlds to possible
histories of the universe, where the space of possible worlds is constrained
by the natures of the objects in the universe (in which we find ourselves).
On the assumption that these objects-including us-are in fact corporeal,
possible worlds can be identified with physically possible arrangements of
the stuff around here. In short, the only possible worlds are the physically
possible worlds; and that's because possible worlds are possible
arrangements of the (basic) objects, all of which are physical.
That was all very fast. In the book, I try to spell it out more slowly, by way
of comparing and contrasting the conceptions of possibility associated with
Kripke, Lewis, and Wittgenstein's Tractatus. But the bottom line is this:
there are no possible worlds where Hesperus isn't Phosphorus; nor are
there any possible worlds where I am a Cartesian soul. I am a
(Strawsonian) person with a corporeal nature; hence, there is no possible
world in which some disembodied soul is me. That said, it's logically
possible that Hesperus isn't Phosphorus; and it's logically possible that I'm a
Cartesian soul. In general, many logical possibilities are (meta)physically
impossible. So we have to drop the following Ludwigian idea: if it's logically
possible that P, there is a possible world where it is true that P. Lewis
(198x) shows how to maintain this idea--along with the contingency of
supervenience--by adopting his kind of modal realism. But we can also drop
this idea, and be a little deflationary about supervenience, given a Kripkean
conception of possible worlds and Fregean conception of 'that'-clauses. The
details, unsurprisingly, resist easy summary.
Still, I hope the basic line of thought is tolerably clear: if you don't think
minds are actually Cartesian thingies that somehow float free of the
physical world, you needn't think that there could have been such thingies.
Kripke offers us a more restrained--and independently more
attractive--conception of modality; and given this conception, one can
endorse global supervenience (as a thesis about how possible worlds are
individuated) without identifying the mental events of people with any
biochemical events in human bodies. People and their mental events can be
primitive, in the sense of being irreducible to anything describable within the
scientific image; yet they can also be supervenient, because that which is
describable within the scientific image determines the space of all possible
worlds-and not just the contingent properties of the world as we find it.
Another large issue remains. Details aside, I say that event C is a cause of
an event E if a fact about C explains a fact about E. (Child has a similar
view.) But if 'explains' is short for 'causally explains', the proposed sufficient
condition is trivial-and presumably not a basis for a substantive thesis in the
philosophy of mind. On the other hand, if we don't pack the idea of
causation into the relevant idea of explanation, why think the proposed
sufficient condition is true? My answer involves appeal to ceteris paribus
laws. Such appeal, however, is bound to raise the concern that I'm trying to
smuggle in a regularity conception of causation. While these themes are in
the background in chapters three and four, chapter seven is where they are
addressed explicitly. And just as I develop Strawson's view of (our concept
of) persons in explicitly distancting myself from Cartesian dualism, I develop
Strawson's view (of our concept of) causation in explicitly distancting myself
Humean views about causation-leaving it open whether Hume was a
Humean.
The idea is to show that: we have a concept of explanation that is a concept
of an objective mind-independent relation R that holds between facts, even
though facts are intentional (and in that sense mind-dependent) objects; at
least where R holds between singular event thoughts, we can speak of a
corresponding relation R* that holds between events; and since events are
mind-independent spatiotemporal particulars, R* is a fully natural relation in
every sense that causation is a natural relation. We can say that R* reflects
an objective and intrinsic feature of each causal sequence. We can-and
should-deny that one event causes another by virtue of some relation (say,
pattern instantiation) that the cause and effect bear to other similar events.
And we can still say (without lapsing into triviality) that C is a cause of an
event E if a fact about C explains a fact about E.
My defense of this position relies on the proposed semantics of causative
verbs; for I suggest that such verbs play an important role in our thinking
about causation and explanation. Unsurprisingly, the proposed account of
ceteris paribus laws also comes into play. (And while there are mentalistic
ceteris paribus laws, it doesn't follow that these will be incorporated into
anything that deserves to be called natural science.) Indeed, for better or
worse, a great deal of the preceeding material is interwoven--or at least
juxtaposed--in chapter seven.
Finally, an appendix addresses some issues concerning mental content. The
idea is to offer an indirect argument for non-Cartesian event dualism: if you
adopt this view, it becomes a little easier to answer certain questions about
mental content, since you're no longer obliged to provide a "naturalistic"
theory of content--i.e., a sufficient condition stated in a nonintentional idiom
for having a mental content. The main chapters do not, however, rely on this
argument.
top | back to symposium index | Introduction Chapter (pdf) |
