profound influences on contemporary philosophy were in the philosophy
of mind and action. This article examines in detail two leading motifs
in Donald Davidson's philosophy. One is that mental phenomena resist
being "captured in the nomological net of physical theory." Davidson
claims there are no strict deterministic laws on the basis of which
mental events can be predicted and explained. He rejects all
deterministic, non-normative laws connecting either mental states with
physical states or mental states with other mental states. The other
motif concerns the problem of analyzing the explanatory force of an
agent's reasons for his or her actions. It is Davidson's contention
that explanation by appeal to reasons is a form of causal explanation,
because this is the only way to account for the fact that we have many
reasons for acting the way we did, but only one of them is the reason
we acted that way.Davidson's argument that mental phenomena can't be
captured by strict, deterministic scientific laws as they are normally
understood, depends upon his treatment of propositional attitudes,
attitudes of hoping that p, or fearing that p, or believing that p,
where p is some proposition. Propositional attitudes have certain
features that distinguish them from physical states and events, says
Davidson. For Davidson there is no "underlying mental reality whose
laws we can study in abstraction from the normative and holistic
perspectives of interpretation." His theory of propositional attitudes
is guided by conclusions drawn from the project of Radical
Interpretation, a project initiated by Quine. Davidson's teacher,
W.V.O. Quine, challenged two central tenets of Logical Positivism:
reductionism and the analytic/synthetic distinction. Following in
Quine's footsteps, Davidson does away with what he considers to be the
third and last dogma of empiricism: the dogma of the dualism of scheme
and reality.
1. Life and Influences
Donald Davidson was born on March 6, 1917 in Springfield,
Massachusetts. He studied English, Comparative Literature and Classics
in his undergraduate years at Harvard, and in his sophomore year he
attended two classes that made a lasting impression on him. These were
two philosophy classes taught by Alfred North Whitehead in the last
year of his career. Afterwards, Davidson was accepted to graduate
studies in philosophy at Harvard, where he studied under Willard Van
Orman Quine. Quine set Davidson on a course in philosophy quite
different from that of Whitehead. Subsequently, Davidson did his
dissertation on Plato's Philebus.
According to Davidson, "The central thesis that emerged was that when
Plato had reworked the theory of ideas as a consequence of the
explorations and criticisms of the Parmenides, Sophist, Theaetetus,
and Politicus, he realized that the theory could no longer be deployed
as a main support of an ethical position, as it had been developed in
the Republic and elsewhere." This dissertation reveals the development
of Davidson's philosophical method and his epistemological position.
Davidson's most profound influences on contemporary philosophy stem
from his philosophy of mind and action. However, Davidson's
philosophical positions in action theory and philosophy of mind are
intrinsically tied into his work on the semantics of natural
languages.
Davidson's apprenticeship in philosophy took place in an intellectual
milieu very different from today's. In the Anglo-American
philosophical community, the middle of the century was dominated by
Logical Positivism. Davidson recalls that he got through graduate
school at Harvard by reading an anthology of Logical Positivism by
Feigl and Sellars. Logical positivism emerged in the Austro-Hungarian
Empire early in this century. Influenced by the logicist project of
Bertrand Russell and Gottlob Frege on the one hand, and by advances in
science on the other, the Logical Positivists of the Vienna Circle
turned to physics as a model of theoretical discourse; and they
considered sensory experiences to be fundamental. Although Logical
Positivism was not entirely a unified movement, the Verification
Principle was shared by most of them. It states that the meaning of
sentences can be accounted for in terms of experiences that would
verify them. Logical Positivism usually promotes a reductionist
program: the reduction of all special sciences to physics, and of all
meaningful statements to reports about sensory experiences. In his
famous paper, Two Dogmas of Empiricism, Davidson's teacher Quine
challenged two central tenets of Logical Positivism: reductionism and
the analytic/synthetic distinction. Following in Quine's footsteps,
Davidson does away with what he considers to be the third and last
dogma of empiricism: the dogma of the dualism of scheme and reality.
See his paper, On the Very Idea of a Conceptual Scheme.
Of the two leading motifs in Donald Davidson's mature philosophy
discussed in this article, one has to do with the fact that mental
phenomena resist being "captured in the nomological net of physical
theory." Davidson rejects strict psychophysical and psychological
laws. The other motif concerns the problem of analyzing the
explanatory force of an agent's reasons for his or her actions. It is
Davidson's contention that explanation by appeal to reasons is a form
of causal explanation.
2. Anomalism of the Mental
Simply put, "anomalism of the mental" amounts to the claim that the
mental is not governed by laws as we usually understand them. In
Davidson's own words:
There are no strict deterministic laws on the basis of which
mental events can be predicted and explained (the Anomalism of the
Mental).
In developing his position, Davidson attempts to retain his
materialism while at the same time to avoid a reductionism. Usually
reductionism has been held to have followed from materialism. When
Davidson asserts that there can be no laws on the basis of which
mental events can be predicted and explained, he has two different
types of laws in mind. In the first type of law, an attempt is made to
link mental states and events with physical states and events, and the
law is used to explain the former on the basis of the latter. Davidson
spends much of his effort in Mental Events showing the impossibility
of such psychophysical laws. In the second type of law, there is an
attempt to formulate strict deterministic laws linking mental states
and events to other mental states and events. Davidson denies the
possibility of these psychological laws as well. Davidson's latter
claim is considered to be a rejection of the most basic goal of the
science of psychology.
In arguing against the possibility of psychophysical laws, Davidson
has in mind the following kinds of laws:
(BL) x (x is in M iff x is in P)
where M denotes some mental state or event and P denotes some physical
state or event. The laws of the above kind are known as bridging laws
(BL). A stronger version of a bridging law claims identity of
properties from different theoretical discourses. A weaker version
claims only that whenever an object instantiates one property it
instantiates the other. An important distinction between laws and
generalizations must be made. There has been general agreement among
philosophers, Davidson included, that a law is distinguished from a
mere generalization by the following features:
1. A law must support counterfactual claims. A law of the form "All
A are B," for instance, is said to sustain the claim that if any
arbitrary x were, contrary to fact, an A, it would also be B.
2. It must be capable of confirmation by observable instances.
To illustrate the difference between generalizations that just happen
to be true, and real laws, consider the following story (adopted from
Jaegwon Kim). Assume that all objects in a fixed domain, for instance
all objects in my room, are either blue or red. In addition, all of
the above objects are considered either edible or inedible. By some
coincidence it so happens that all red objects in my room are edible.
Perhaps the red objects in my room are either ripe tomatoes or ripe
cherries. This allows us to form a true generalization about this
fixed domain:
(G) If x is red then x is edible.
It is obvious that (G) does not support counterfactual conditionals.
For instance (G) does not allow us to infer of some green object (say
a copy of Davidson's Essays on Actions and Events) that if it were red
it would be edible. Davidson is quite explicit that his attack is
aimed at psychophysical laws not at true psychophysical
generalizations:
The thesis is rather that the mental is nomologically irreducible:
there may be true general statements relating the mental and the
physical, statements that have the logical form of a law; but they are
not lawlike (in a strong sense to be described). If by absurdly remote
chance we were to stumble on a non-probabilistic, true, psychophysical
generalization, we would have no reason to believe it more than
roughly true; we would have no reason to believe it was a law.
Following this view, it is important to keep in mind the fact that
whether any given psychophysical generalization is true is a
contingent, empirical matter. As we will see later, it is an a priori
matter for Davidson that no such generalization can be a law.
The core idea of Davidson's argument against the possibility of
psychophysical laws can be found in the following passage:
Nomological statements bring together predicates that we know a
priori are made for each other — know, that is, independently of
knowing whether the evidence supports a connection between them. If we
can know a priori when the predicates are made for each other, then we
can know by the same token when they aren't. Davidson finds that it is
an a priori truth that mental and physical predicates are not made for
each other. Here is the structure of his argument.
1. Both mental and physical phenomena have distinct sets of
features characteristic of their own domains, but these features are
incompatible with each other.
2. Bridging laws linking properties from two distinct theoretical
discourses (in this case mental and physical) would transmit
properties from one discourse to another, which in case of mental and
physical phenomena would lead into incoherence.
3. Therefore, there could be no psychophysical laws linking mental
and physical phenomena.
According to Davidson, the paradigmatic criterion of the mental events
is their susceptibility to the description "in terms of vocabulary of
propositional attitudes." Propositional attitudes, or intentional
states as they are sometimes called, are various cognitive attitudes;
we can have hope that the proposition p is true, we can fear that p is
true, we can desire that p is true, and so forth. You and I can have
different attitudes toward the proposition "Snow is white." I hope
that snow is white, whereas you believe that it is but don't hope it
is. The proposition itself, namely, that snow is white, towards which
one has an attitude is said to give the content to one's mental state.
Propositional attitudes have certain features (or are constrained by
certain principles) that distinguish them from physical states and
events. Davidson's theory of propositional attitudes is guided by
conclusions drawn from the project of Radical Interpretation, a
project initiated by Quine. Imagine that you have encountered a group
of people in an unfamiliar land who display what appear to you to be
shared verbal and non-verbal behavior. What do they mean when they
point at a rabbit running by and say, "Gavagai"? Interpreting their
behavior by assigning meaning to their actions (of which linguistic
utterances is a subclass) is the task of Radical Interpretation. The
principles and techniques we would apply in the above described
situation are not unlike the principles and techniques we commonly
apply in interpretation of other people's actions and utterances whose
language we already share. Radical Interpretation, according to
Davidson, is guided by normative principles and must proceed
holistically:
This method is intended to solve the problem of the
interdependence of belief and meaning by holding belief constant as
far as possible while solving for meaning. This is accomplished by
assigning truth conditions to alien sentences that make native
speakers right when plausibly possible, according, of course to our
own view of what is right.
These general normative principles that guide the task of Radical
Interpretation, and therefore constrain the task of attribution of
propositional attitudes, are principles such as "Don't believe an open
contradiction", or "If you believe that p and q, then also believe
that p." It is important to keep in mind the fact that intentional
states are capable of justifying other intentional states. In physical
theory the movement of one ball is explained by the movement of the
other. Having a belief that pressing on a lever will stop the flow of
water doesn't just explain my action of stopping the flow of water.
This belief (together with the desire to stop the flow of water) also
justifies my action in the sense that it makes it reasonable in the
light of the above belief. (Intentional states justifying other
intentional states will be discussed further in the second part of
this article.) Davidson is explicit that it is a part of what it is
for something to be a propositional attitude (like a belief) that it
be subject to these normative principles. This makes these principles
a priori and necessary constitutive of the concept of propositional
attitudes. In contrast, our knowledge of things physical is a
posteriori and contingent in nature.
So far, we have spent time explaining the normative character of the
mental and have discussed that the interpretation must proceed
holistically:
There is no assigning beliefs to a person one by one on the basis
of his verbal behavior, his choices, or other local signs no matter
how plain and evident, for we make sense of particular beliefs only as
they cohere with other beliefs, with preferences, with intention,
hopes, fears, expectation, and the rest.
It can be seen from the above remark that interpretation is holistic
in the sense that the attribution of each individual mental state to
another person must be made against the background of attribution of
other mental states. In addition, the attribution to an agent of the
entire system of propositional attitudes is further constrained by
considerations that involve maximization of coherence and rationality.
Davidson is quite aware of the fact that holism and interdependence
are common to physical theory. In physical theory such a priori facts
as the transitivity of "longer than" is what makes physical
measurements possible. Thus, the physical realm is also characterized
by the a priori laws constitutive of our conception of the physical.
What sets the realms of the mental and the physical apart is the
disparate commitments of each realm. Rationality and the governing
normative principles are essential characteristics of the mental.
Thus, the absence of rationality and normative principles is a
characteristic of the physical. If there were bridging laws, we would
find, unhappily, that the characteristics of the mental that have "no
echo in physical theory" would be transmitted to the physical and vice
versa. In the first of the above scenarios we would have to apply the
Principle of Charity with its rule of maximization of coherence and
rationality to the physical, which, according to Davidson, is plainly
absurd. In the second scenario we would have the principles governing
the attribution of the mental be preempted by the merely physical
constraints. This happens for the following reason: if there were
bridging laws of the type (BL), then neural states of the brain would
be nomologically coextensive with certain intentional states. But
neural states (being theoretical states of physical theory) are
governed by conditions of attribution that in turn are regulated by
the constitutive rules of the physical theory. Thus, constitutive
rules of the mental are ignored in this scenario. Davidson concludes
that:
There are no strict psychophysical law because of the disparate
commitments of the mental and physical schemes. It is a feature of
physical reality that physical change can be explained by laws that
connect it with other changes and conditions physically described. It
is a feature of the mental that the attribution of mental phenomena
must be responsible to the background of reasons, beliefs, and
intentions of the individual. There cannot be tight connections
between the realms if each is to retain allegiance to its proper
source of evidence.
It is important for Davidson to note that the mental does have its own
laws, for instance, the laws of rational decision making. The crucial
difference between such laws and the laws that could be counted as
psychophysical is the difference between the normative character of
the former and the predictive power of the latter. When anomalism of
the mental denies the existence of psychophysical and psychological
laws, the sense of "law" is taken to involve strict nomological
predictions and explanations of behavior. Thus, normative "laws" are
quite compatible with anomalism of the mental. An interesting question
is whether Davidson's notion of what constitutes a "law" has merit
won't be discussed here.
The claim of the anomalism of the mental consists of two subsidiary
claims. Thus far we have considered the support for the claim that
there are no psychophysical laws. Davidson also defends the claim that
there could be no precise psychological laws, that is, there are no
precise laws that relate mental states and events to other mental
states and events. The argument for this claim can be found in
"Psychology as Philosophy." As the title suggests, Davidson intends to
contrast the claim that psychology is more like philosophy with the
claim that it is more like science and then refute the latter claim.
One point deserves special attention before we proceed to the exegesis
of Davidson's argument against psychological laws. Actions, although
undeniably physical under some descriptions, are considered to be
mental by Davidson. This is so because, when we state which action
someone is performing versus merely describing the physical movement
his body is undergoing, we are contributing an interpretation of him
and interpretation, as we have seen, is guided by certain normative
constraints. Thus, the laws that could relate an agent's mental states
to his actions would count as psychological laws.
The gist of the argument against psychological laws can be found in
the following passage:
It is an error to compare truisms like "If a man wants to eat an
acorn omelette, then he generally will if the opportunity exists and
no other desire overrides" with a law that says how fast a body will
fall in a vacuum. It is an error, because in the latter case, but not
the former, we can tell in advance whether the condition holds, and we
know what allowance to make if it doesn't.
If the above truism were a psychological law, then for the antecedent
to obtain, the agent must want to eat an acorn omelette. But our
knowledge of an agent's desires crucially depends upon our attribution
of other mental states to him (or her). In addition, knowing his
action subsequent to his desire will help us interpret whether the
agent had the desire in the first place. Thus both the antecedent and
the consequent of the supposed psychological law are related to each
other through the holism of interpretation.
What is needed in the case of action, if we are to predict on the
basis of desires and beliefs, is a quantitative calculus that brings
all relevant beliefs and desires into the picture. There is no hope of
refining the simple pattern of explanation on the basis of reasons
into such a calculus.
Since no such hope exists, any psychological generalization purporting
to be law must rely upon generous escape clauses such as "if no other
desire overrides," ceteris paribus, and so forth. The necessity of
such fail-safe clauses is dictated by the fact that for Davidson there
is no "underlying mental reality whose laws we can study in
abstraction from the normative and holistic perspectives of
interpretation."
3. Causal Explanation of Action
Actions, according to Davidson, are events. Events, in his ontology,
are particular dated occurrences; the essential feature of which is
susceptibility to redescription. In order to admit an entity into
one's ontology, one must specify the conditions of individuation for
that entity. On Davidson's view:
[E]vents are identical if and only if they have exactly the same
causes and effects.
This criterion may seem to have an air of circularity about it, but if
there is circularity it certainly is not formal. For the criterion is
simply this: where x and y are events,
x = y if and only if [(z) (z caused x implies z caused y) and (z) (x
caused z implies y caused z)].
It is important to keep in mind that for an event to be an action, the
event must be describable in a specific way. Actions are events that
people perform with intentions and for reasons. One and the same
action can be specified as intentional under some description and as
purely physical under another description. But in order to be an
action an event must have at least one description under which it is
specified as intentional. The above requirement for an action hinges
on the larger distinction between specifying the whole of an event
with wholly specifying it. The distinction comes up in the context of
the discussion of causation and causal explanation:
The salient point that emerges so far is that we must distinguish
firmly between causes and the features we hit on for describing them,
and hence between the question whether a statement says truly that one
event causes another and the further question whether the events are
characterized in such a way that we can deduce, or otherwise infer,
from laws or other causal lore, that the relation was causal.
In the case of one event causing another, any description that picks
out the right event specifies the whole of the cause. Some
descriptions, of course, will be richer in the information they
disclose about an event. This richness should not affect in any way
how much of a cause they refer to. The story is quite different when
it comes to what Davidson calls "the further question" of causal
explanation. Causal explanations are by their very nature attempts to
explain events in terms of the causes of these events. But, according
to Davidson, causal explanations are, in addition, sensitive to how
the events in question are described. For instance, the two
descriptions "Jack's walking in the room" and "Jack's stomping in the
room" may refer to the same event that caused Jill to wake up. However
the latter may serve as a causal explanation of Jill's waking up,
whereas the former may not.
One of Davidson's major contributions to philosophy of action is his
claim that explanation via reasons is a form of causal explanation. In
order to understand Davidson's claims that reasons are the causes of
the actions that they are reasons for and that "reason explanation" is
a form of causal explanation, we must understand how on his view
causal explanation works.
One theory of causal explanation arises out of Hume's position that
wherever there is a causal relation between two distinct events a and
b there must be a law relating two types of events A and B that the
events in question instantiate. This position has been further
developed in the middle of the twentieth century by Carl Hempel into
the deductive-nomological theory of explanation (DN from now on).
According to DN, an event E is causally explained just in case the
statement asserting the occurrence of E deductively follows from
1. the statement asserting the occurrence of its cause C , and
2. the statement of some general causal law L.
The opponents of the DN model argue that one can judge that an event a
caused an event b without knowing the laws that these events
instantiate. Davidson contends that the opposition between the
opponents and the champions of the DN model is more apparent than
real. The solution to the conflict depends on the distinction between
events and their descriptions:
Causality and identity are relations between individual events no
matter how described. But laws are linguistic; and so events can
instantiate laws, and hence be explained or predicted in the light of
laws, only as those events are described in one or the other way.
In short, Davidson lends his support to the principle of Nomological
Character of Causality. This principle says that "when events are
related as cause and effect, they have descriptions that instantiate a
law. It doesn't say that every true singular statement of causality
instantiates a law." It is worth noting that Davidson accepts this
principle on faith, as many commentators have pointed out. Unlike
David Hume, who accepts the principle because his analysis of the
nature of causation as a constant conjunction requires it, Davidson
disavows analyzing the nature of causation itself. His goal,
explicitly stated, is to provide an analysis of the logical form of
causal statements.
We can now turn to the question of the causal explanation of action
and briefly discuss Davidson's impetus for his claim that reason
explanation must be a form of causal explanation. Davidson's opponents
(the anti-causalists) on the explanation of actions claim that reason
explanation is different in kind from causal explanation. There are
two main types of arguments for the anti-causalist position:
methodological and conceptual. Anti-causalists who rely on
methodological arguments for their position, claim that a DN model
that relies on the concept of lawful regularity has a place only in
the physical sciences. By contrast, the primary constraint placed on
explanation in the social sciences is a normative one. Thus, lawful
regularities relating reasons to actions would be simply irrelevant to
explanation in social sciences, according to anti-causalists.
Conceptual arguments are meant to establish the stronger claim that
reasons cannot in principle be causes. One plausible argument of the
conceptual variety rests on the assumption that "the presence of a
reason cannot be ascertained independently of the occurrence of the
action it rationalizes." This, presumably, leads to the disparate
evidential commitments of the causal explanation and reason
explanation. Davidson himself appears to advocate the above point in
the passage quoted above. Thus, all arguments against the causalist
position, including the ones briefly mentioned, revolve around the
normative constraints placed on the explanation of the mental.
In short, an explanation of an agent's action can be considered
adequate only if it shows the action in question to be reasonable
against the background of an agent's beliefs and desires. This latter
condition together with the truth condition, which states that the
propositional attitudes a rationalization attributes to an agent must
be true, form the necessary conditions for the justification model of
explanation. Davidson considers the above conditions necessary but not
sufficient. The deficiency of the justification model is explained by
drawing attention to the distinction between having a reason for an
action and having the reason why one performs an action. For a reason
to be the reason why one performs an action the reason must cause the
action. For example, one has a reason to turn on the television, say,
to watch one's favorite TV show. But this need not be the reason why
one turns on the television. This is because the above reason did not
cause one to turn on the television. As Davidson puts it:
[S]omething essential has certainly been left out, for a person
can have a reason for an action, and perform the action, and yet this
reason not be the reason why he did it.
In our example, the reason for one to turn on the television, let's
say, is that one is lonely and company. Thus, one reason (namely, to
keep one company) was the cause of the action while the other reason
(namely, to watch one's favorite show) wasn't. Davidson continues:
Of course, we can include this idea too in justification; but then
the notion of justification becomes as dark as the notion of reason
until we can account for the force of that "because."
The mere possibility that a person acted on the basis of one reason
rather than another presents an insurmountable obstacle. The
anti-causalist has no way of accounting for the force of the "because"
in the rationalization. Thus, the justification model is silent on
what would count as the correct rationalization. The only solution,
according to Davidson, is to view the efficacious reasons (the ones
that account for the correct rationalization) as causes of action.
This leaves us, according to Davidson, with only one alternative to
justificationalism, namely, the view that reason explanation is a
species of causal explanation.
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