Post on 27-Dec-2015
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All my course outlines and PowerPoint slides can be downloaded from: http://www.freewebs.com/mphk2/
Friday, November 16th: NO LECTURE
Friday, November 23rd:
3-4pm: Lecture 7: Practice
Coffee, tea and biscuits!!!
4-5pm: Lecture 8: Values and Critical Theory
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LECTURE 5: LAWS IN THE SOCIAL SCIENCES?
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§1. Introduction: Hempel on Explanation and Prediction in History (Hempel (1942/1994)
L1, L2, … Ln
C1, C2, … Cn
-----------------
E
} Explanans
Explanandum
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Why don’t explanations in history have this form:
• The laws are sometimes trivial.
• The laws are sometimes too complicated to state.
Note:
• The laws often come from other fields.
• Often we get only explanation sketches.
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§2. Laws and Complexity (Hayek 1967/1994; Scriven 1956/1994; McIntyre 1993/1994)
• The social world is intrinsically too complex for laws. – Hayek
• The level of description of the social world that interests us is too complex for laws. – Scriven
• Why can’t we change the language and analysis even at the level we are interested in? – McIntyre
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§4. Reconstruction of Davidson’s
“Psychology as Philosophy” (1974)
Often presented as an argument against the possibility of laws in the social sciences …
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[1] Main thesis: There can be no (strict causal) laws in (intentional) psychology.
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Mind-Body Identity ThesisMind-Body Identity Thesis
== ==== == ======== ==
tok
ens
tok
ens Mental Mental
PhysicalPhysical
Tokens are spatio-temporal particulars.Tokens are spatio-temporal particulars.
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Type materialismType materialism::
== ==== == ======== ==
tok
ens
tok
ens Mental Mental
PhysicalPhysical
Mental Mental type Atype A
Mental Mental type Btype B
Physical Physical type 1type 1
Physical Physical type 2type 2
A= 1; B = 2 …A= 1; B = 2 …
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Token materialismToken materialism::
== ==== == ======== ==
tok
ens
tok
ens Mental Mental
PhysicalPhysical
Mental Mental type Atype A
Mental Mental type Btype B
Physical Physical type 1type 1
Physical Physical type 2type 2
A≠ 1; B ≠ 2 …A≠ 1; B ≠ 2 …
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[7] Strict causal laws exist only in closed and deterministic systems.
There are physical strict causal laws, since the physical realm is closed.*
*At least for materialists – this argument is based upon materialist premises.
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[8] Does that mean that there are no (strict causal) laws covering intentional psychology?
After all, the psychological realm is not closed.
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[9] But does not materialism allow for a different answer?
If psychological entities are (identical with) physical entities then they are part of a closed system.
Like this …
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Psychological law:
Psych. event type A causes psych. event type B.
Psychophysical laws:
A=C B=D
Physical law:
Brain event type C causes brain event type D.
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[10][10] Bel[q]Bel[q] Bel[r]Bel[r] Bel[s] Bel[s]
| | ||
Bel[p]Bel[p] || ????
||Bst[p]Bst[p] || ||
Bst[q]Bst[q] Bst[r]Bst[r] Bst[s]Bst[s]
Rationality Rationality as “constitu-as “constitu-tive idea” … tive idea” … consistency, consistency, coherence …coherence …
““No echo”No echo”
HolismHolism
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Problem: the intentional states are related by normative relations (of consistency, coherence, rationality) and these normative relations have “no echo” in the physical realm.
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Kincaid:
• Davidson gives us no good reasons against laws:
“… much social science proceeds at the macro-level ... As such, it is unaffected by the failure of specific theories of individual behavior. ...” (115)
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LECTURE 6: ACTION EXPLANATIONS, REASONS, AND CAUSES
Davidson: “Actions, Reasons, and Causes”, 1963
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§0. Introduction
Claim: The social and the natural sciences differ fundamentally in their modes of explanation:
Natural sciences: causal explanations
Social sciences: non-causal explanations in terms of reasons.
Is that true?
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§1. Preliminary I: Intensional vs. Extensional Contexts
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A sentence S is an extensional context iff:
(a) Intersubstitutivity salve veritate: Co-referring expressions can be substituted for one another
in S without that S’s truth value changes.
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A sentence S is an extensional context iff:
(a) Intersubstitutivity salve veritate: Co-referring expressions can be substituted for one another
in S without that S’s truth value changes.
Co-referring expressions: “Martin Kusch” and “Sarah Gore’s husband”
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A sentence S is an extensional context iff:
(a) Intersubstitutivity salve veritate: Co-referring expressions can be substituted for one another
in S without that S’s truth value changes.
Co-referring expressions: “Martin Kusch” and “Sarah Gore’s husband”
If
“Martin Kusch lives on Alpha Road”
is true, then so is
“Sarah Gore’s husband lives on Alpha Road”.
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A sentence S is an extensional context iff:
(b) Existential generalisation: S entails the existence of the entities to which its expressions refer.
If “Martin Kusch lives on Alpha Road”
is true, then Martin Kusch exists.
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A sentence S is an intensional context if, and only if, both (a) and (b) fail.
(a) “Mary believes that Martin Kusch lives on Alpha Road”
does not entail that
“Mary believes that Sarah Gore’s husband lives on Alpha Road”.
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A sentence S is an intensional context if, and only if, both (a) and (b) fail.
(a) “Mary believes that Martin Kusch lives on Alpha Road”
does not entail that
“Mary believes that Sarah Gore’s husband lives on Alpha Road”.
(b) Nor does it entail that Martin Kusch exists.
(Mary might be wrong to believe that I’m alive.)
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“Intentional” ≠ “intensional”!
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§2. Preliminary II:
Action Descriptions, Justification and Intensionality
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• Whether an action is justifiable depends on how it is described.
• Take my action of opening the window.
• We can re-describe this action as the action of letting in fresh air.
• This seems to provide a justification of the action (of opening the window).
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• But we can also re-describe the same action as the action of giving the audience a cold.
• Under this description the action (of opening the window) is not justifiable.
• Thus, we cannot substitute one action description for another without changing the value of the action.
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§3. Preliminary III: Davidson on Causation
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Causal relations are part of the world;
causal relations hold between particular events;
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Causal relations are part of the world;
causal relations hold between particular events;
Causal explanations are part of language;
causal explanations hold between statements or descriptions of events and laws.
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Singular causal statements vs. causal explanations
In singular causal statements the expression “caused” relates not sentences but particular events.
“The short circuit caused the fire.”
Event1 Event2
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Singular causal statements are extensional contexts:
If the fire was mentioned at 8am on the Today Programme on 19/10/07, we can replace
The short-circuit caused the fire
by
The short-circuit caused the event mentioned at 8am on the Today Programme 19/10/07
– without changing the truth-value.
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Cf. a causal explanation of the fire. According to the standard deductive-nomological account, we explain an event by deducing it from laws of nature and statements describing various circumstances before and during the event.
L1 …. Ln
C1 … Cn Explanans ------------------ Explanandum
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• Deduction takes us from sentences to sentences.
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• Deduction takes us from sentences to sentences.
• Whether or not a deduction (within a causal explanation) is possible, depends crucially on how we describe the cause and the effect.
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• Deduction takes us from sentences to sentences.
• Whether or not a deduction (within a causal explanation) is possible, depends crucially on how we describe the cause and the effect.
• While there are natural laws from which we can deduce “The short-circuit caused the fire”, …
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• Deduction takes us from sentences to sentences.
• Whether or not a deduction (within a causal explanation) is possible, depends crucially on how we describe the cause and the effect.
• While there are natural laws from which we can deduce “The short-circuit caused the fire”, …
• … there are no natural laws from which we can deduce “The short-circuit caused the event
mentioned at 8:15am on the Today Programme on 19/10/07”.
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Causal explanation is intensional.
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§4. Preliminary IV: Rationalisations of Actions
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• Consider the action described as:
“Mary came to the lecture”.
• Why did she?
E.g. (*)
“… because it is on Davidson.”
• (*) provides a reason for Mary’s action; it is a rationalisation of her action.
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• (*) refers to a “pro-attitude” (desire, wish ...) and to a belief (Davidson):
• Pro-attitude: Mary desires to learn about Davidson today.
• Belief: Mary believes that if she comes to today’slecture, she will be able to learn about Davidson.
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• How do we know that, although Mary had the mentioned reason, she didn’t act on another one?
• She might have any number of reasons.
• Which one moved her?
• According to the received view, the difference between having and acting on a reason is causal.
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§5. The Anti-Causalists
Anscombe, Winch, Melden, Dray, von Wright …
The difference cannot be causal!
Reasons cannot be causes!
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[1]
On a Humean view of causation, two events relate as cause and effect if, and only if, they instantiate a law of nature.
But we do not have laws of nature covering the relationship between reasons and actions.
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[2]
On a Humean view of causation, causal relations are strictly different from logical or conceptual ideas.
But in a rationalisation the relationship between the reason and the explained action is conceptual and logical (or “internal”).
Cf.: The “Logical Connection Argument” (here is von Wright’s version):
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Agent X intends to bring about [state of affairs] p.
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Agent X intends to bring about [state of affairs] p. X considers that he cannot bring about p unless he does action a.
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Agent X intends to bring about [state of affairs] p. X considers that he cannot bring about p unless he does action a. Ergo: X sets himself to do a.
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Agent X intends to bring about [state of affairs] p. X considers that he cannot bring about p unless he does action a. Ergo: X sets himself to do a.
Premises and conclusion are conceptually dependent:
The verification of the premises presupposes the verification of the conclusion, and the verification of the conclusion presupposes the verification of the premises. (von Wright 1971).
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§6. Davidson’s Causalist Response
(“Actions, Reasons, and Causes”, 1963)
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“Rationalisation is a species of causal explanation.”
A rationalisation has two aspects:
[i] it justifies the action – the aspect of rationality
[ii] it explains the action causally – the aspect of causality
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Consider [i] first. How is this to be analysed further:
Note first of all that we always do intentional actions under a description …
X has a primary reason to do action a under description d, if, and only if:
[1] X has a pro-attitude (wish, desire, etc.) towards actions with property p;
[2] X has the belief that action a, under description d, has this property p.
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MK has a primary reason to do the action of window-opening under the description ‘letting in fresh air’, iff:
[1] MK wishes for actions that have the property of keeping his students awake;
[2] MK believes that the action of window-opening under the description ‘letting in fresh air’ has the property of keeping his students awake.
“The primary reason of an action is its cause.” (Davidson)
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[1] Recall Objection One: There are no laws concerning reasons and actions.
Davidson agrees with that point to some extent (cf. L.5):
“... generalisations connecting reasons and actions are not – and cannot be – sharpened into the kind of law on the basis of which accurate predictions can
reliably be made” (683).
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But remember that
(1) reasons are psychological states (or events), and
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But remember that
(1) reasons are psychological states (or events), and
(2) tokens of psychological states (events) are identical with tokens of physical states
(events) of the brain.
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But remember that
(1) reasons are psychological states (or events), and
(2) tokens of psychological states (events) are identical with tokens of physical states
(events) of the brain.
(3) And there are strict physical (brain-physiological) laws that govern states
and events in the brain.
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• Take two event tokens a and b.
• When we want to claim a causal relation between a and b, we have to describe a and b in some way.
• More than one description is usually possible.
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• Hume’s insistence that singular causal statements must be ‘backed’ by a causal law amounts to this:
“‘a caused b’ entails that there exists a causal law instantiated by some true descriptions of a and b”.
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E.g. “This primary reason [i.e. (token) belief and pro-attitude] caused this action” claims a causal relation between two events (the primary reason and the
action).
There can be no intentional-psychological law that backs up this singular causal claim.
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But there exists a causal law governing the relationship between the two token events nevertheless: a brain-physiological law.
In order to make explicit we have to re-describe the two events tokens in brain-physiological terms.
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reasonreasontokentoken actionactiontokentoken
RationalityRationality
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physical eventsphysical eventstokentokenbrainstatebrainstatetokentoken
CausalityCausality
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reasonreasontokentoken
physical eventsphysical eventstokentokenbrainstatebrainstatetokentoken
actionactiontokentoken
RationalityRationality
CausalityCausality
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Token materialismToken materialism::
== ==== == ======== ==
tok
ens
tok
ens Mental Mental
PhysicalPhysical
Mental Mental type Atype A
Mental Mental type Btype B
Physical Physical type 1type 1
Physical Physical type 2type 2
A≠ 1; B ≠ 2 …A≠ 1; B ≠ 2 …
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Token materialismToken materialism::
== ==== == ======== ==
tok
ens
tok
ens Mental Mental
PhysicalPhysical
Mental Mental type Atype A
Mental Mental type Btype B
Physical Physical type 1type 1
Physical Physical type 2type 2
A≠ 1; B ≠ 2 …A≠ 1; B ≠ 2 …
CAUSES
CAUSES
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[2] Objection Two: The Logical Connection Argument
We need to distinguish between events (i.e. the ontological level) and their description (i.e. the linguistic level).
Consider:
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[a] The short-circuit caused the fire.
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[a] The short-circuit caused the fire.
[b] The short-circuit = the cause of the fire.
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[a] The short-circuit caused the fire.
[b] The short-circuit = the cause of the fire.
[c] The cause of the fire caused the fire.
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[a] The short-circuit caused the fire.
[b] The short-circuit = the cause of the fire.
[c] The cause of the fire caused the fire.
Now the relation is logical-conceptual!
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[a] The short-circuit caused the fire.
[b] The short-circuit = the cause of the fire.
[c] The cause of the fire caused the fire.
Now the relation is logical-conceptual!
But only on the level of the description!!!
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Rationalisations describe two events (the reason and the action) in ways that make their
relationship internal, conceptual or even logical.
But there is always a different level of description too – the level of brain-physiology – and on that level the relationship is external.
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Insofar as they explain the occurrence of the action, rationalisations are singular causal statements.
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Insofar as they explain the occurrence of the action, rationalisations are singular causal statements.
And singular causal statements are extensional.
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Insofar as they explain the occurrence of the action, rationalisations are singular causal statements.
And singular causal statements are extensional.
Hence they remain true when we replace the intentional-psychological descriptions with brain-physiological descriptions.
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So, for Davidson, action explanations have two aspects: they justify and they explain causally. But these two aspects are kept apart.
Reasons do not cause actions in virtue of justi-fying them but in virtue of their instantiating a
strict physical law.
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Psychological law:
Psych. event type A causes psych. event type B.
Psychophysical laws:
A=C B=D
Physical law:
Brain event type C causes brain event type D.
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Psychological claim:
psy. event token A causes psy. event token B.
Psychophysical laws:
none
Physical law:
Brain event type C causes brain event type D.
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§8. The Anti-Causalist’s Return? (Stoutland 1988)
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[1] If Davidson is right, we can never know whether a given reason caused a given action.
For in order to know that we need to know the strict physical law according to which (re-
described as physical events) the reason caused the action. But we do not know such laws!
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[2] “The difference between rationalising our behaviour and explaining it in terms of reasons is not causal but normative, and normative all the way down.”
The reason you act on is one of the reasons that you have, and it is the reason that it is most rational to act on in present circumstances.
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[3] It is wrong to think that reasons for actions must be mental states.
Mary’s coming to the lecture can be justified by the fact that the lecture is on Davidson.
This fact also explains why Mary comes to the lecture, provided only that she meets the pre-condition of believing the fact.
But her mental state is merely a precondition for the justification to function as an explanation. It is not part of the explanation.
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It does become part of the explanation only when her belief is false. Consider the answers we give to
“Why did Mary come to the lecture?”
“Because the lecture is on Davidson.” (No mental states mentioned here.)
“Because she falsely believed that the lecture is on Davidson.”
(Mental state mentioned.)
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§9. Tentative Conclusion
There may be after all grounds for the claim according to which the social and the natural sciences differ in their modes of explanation.
– This deals a (further) blow to the unity-of-science thesis.