[ Nancy Cartwright (1989), Nature’s Capacities and Their Measurement (Oxford: Clarendon Press), pp. 141-182. ]
4.1. Introduction
4.2. Why Should Increases in Probability Recur?
4.3. Forecasting and the Stability of Capacities
4.4. Beyond Modality
4.5. Mill in Defence of Capacities
4.6. Conclusion
4.1. Introduction
p.141 #1
- Cartwright wants to argue that
(i) in addition to the notion of law, we also need the concept of capacity; and
(ii) just as causal laws are not reducible to functional and statistical laws, so too ascriptions of capacity are not reducible to causal law.
p.141 #2
- 그 이유
- The phrase ‘because of being aspirins’ is meant to express a fact about property and not about individuals.
- the property of being an aspirin carries with capacity.
p.142 #1
general causal truths not reducible to associations
capacity
a causal law
generality
p.142 #2
- the concept of capacity assumes that statistics are supposed to tell us about causes.
p.142 #3
- the crucial question for empirist is the question of testing.
- 측정 방법은 이미 ch1과 sec2.4.에서 제시
4.2. Why Should Increases in Probability Recur?
p.142 #4
- Principle CC (Principle of common cause)
- Principle CC says that ‘C causes E’ iff the probability of E is greater with C than without C in every causality homogeneous background.
- Principle CC에서는 every homogeneous background를 상정
카트라이트는 이 보편 양화사(every)를 사용하는 인과 개념이 너무 강한 개념이라고 논증함
p.143 #1
- John Dupré says, causes have contextual unanimity in every homogeneous background.
- dual capacity의 예: In Hesslow’s example, birth-control pills have dual capacities.
p.144 #1
- 3장에서 카트라이트는 Eells와 Sober의 CC가 아니라 CC*를 주장함
- Cartwright’s argument
: an increase in probability of E on C in one of the specially selected populations.
-> in those special test populations, in can be regularly relied on that some Cs will produce Es.
p.144 #2
- 카트라이트의 정의
‘causal laws’: a very local kind of causal claim
(if in a given test population we see the increase in probabilities, that guarantees that Cs causes Es there in that population.)
- What make the causal law true that C causes E in T is not the increase in probability of E with C in T, but rather the fact that in T some Cs do regularly cause Es.
- Laws are not revealed in the probabilities.
p.145 #1
- ‘Cs cause Es in T’ -> ‘Cs cause Es’
- It means that C carries the capacity to produce E.
p.145 #2
- Cartwright’s thesis: to believe in contextual unanimity is to believe in capacities.
p.146 #1
- contextual unanimity is a very peculiar concept for a Humean.
p.146 #2
- With all the work on possible-world semantics, philosophers become used to laws of nature, and counterfactual.
- All As are Bs by laws. This law allow us to infer from one empirical fact(A) to another(B). We are able to know this second empirical fact(B) without anybody ever having to look.
p.146 #3
- Just as laws constrain relations between matters of fact, capacities constrain relations among laws. It means that one can infer one causal law directly to another, without ever having to do more test.
- A property carries its capacities with it, form situation to situation. Capacities are much like essences.
p.146 #4
카트라이트의 세 가지 논점 요약
p.147 #1
- modality as an inference license
- ascriptions of capacity are at a higher level of modality than causal laws.
(i) ascriptions of capacity licence stronger inferences
(ii) they make stronger presuppositions about the stability and regularity of nature
- a distinction between causal laws and ascriptions of capacity
- Causal laws can be inferred form the probabilities that obtain in those situations. A capacity claim supposes that the causal possibilities continue to obtain in various different kinds of situation.
- 가능한 입장: 귀납을 허용하는 두 가지 입장
p.147 #2
- 귀납에 관한 카트라이트의 입장: induction never enters.
- The logic of testing is a bootstrap logic.
p.147 #3
ch1과 관련 (다시 보아야 함)
p.148 #1
ch1, 2, 3에 등장하는 것 모두 data+background assumption에서 causal conclusion을 얻는 논증이 연역적이라는 것
4.3. Forecasting and the Stability of Capacities
p.148 #2
- The linear equations provide a rigorous ground for standard probabilistic measures of causality.
- a distilled version of what Haavelmo and Frisch wre doing
p.149 #1
- a price-demand curve
: D
q = αp+u
q: quantity demanded
p: price
u: some kind of random shock which turns the equation from a deterministic relationship into a probabilistic one
α: fixed parameter
p.149 #2
- First, this equation is supposed to represent a causal relationship, not a mere functional one.
p.149 #3
e.g. Marschak가 기술한 경제학의 방정식의 네 가지 특징
p.150 #1
- 네 가지 특징 중 두 번째 특징
: the random terms reflect the influences of erratic causes.
p.150 #2
This equation assumes that the price has a stable tendency to influence demand, and that that tendency has a fixed and measurable strength. This is what is represented by the α.
p.150 #3
- α represents the price elasticity of demand.
- 마셜은 α가 변한다고 보았고 계량경제학자는 α가 안 변한다고 봄.
- the two view are reconcilable.
p.151 #1
- the assumption of stability is built into the demand equation.
p.151 #2
- the demand equation does not represent a deterministic relationship between p and q. Instead, there will be some probability distribution for the two.
- five parameters: 𝜇ₚ, 𝜇q, 𝜎ₚ, 𝜎q, p
𝜇ₚ = 0 = 𝜇q
𝜎ₚ = 1 = 𝜎q
(recall from ch2)
𝑞 = 𝜌𝑝+𝑢
p.151 #3
- an old question in causal-modelling theory: what is the point of the equation?
- a conventional answer: the equations express a commitment about what remains constant under change.
e.g. α = Exp(pq)/Exp(𝑝²) = 𝑝/𝜎ₚ²
(i) Exp(pq) stays fixed no matter what the variance in p is.
(ii) Exp(pq) is always varied in just the right way to keep α fixed.
p.152 #1
약간 다른 상황
D’ : q = αp+βr+u
- whether r is there or not, we assume that α stays the same. It is peculiar.
p.152 #2
p.152 #1
- Parameters are estimated in one context, and these values are assumed to obtain in entirely different contexts.
p.153 #2
- given the constraint on the form, the theory itself can be inferred from the data.
- In econometrics the theory is not constructed from the ‘raw’ data, but rather from the ‘interpreted’ data, or probabilities, that these frequencies are used to estimate.
p.153 #3
- Econometricians’s fundamental concern is: will the parameters continue to hold under various innovations.
p.154 #1
e.g. Robert Lucas
p.155 #1
Haavelmo의 개념
: autonomous laws and non-autonomous laws
p.156 #1
- in the truly fundamental equations the parameters would be independent.
p.156 #2
- one of the most critics of econometrics was Keyens.
Lucas’s arguments are based on reflections on the relationship between the more autonomous laws(the micro-level) and the less autonomous laws(the macro-level).
p.157 #1
- Keynes proposes a very different kind of world: not an atomistic but a wholistic world.
- This would not be a world in which capacities operate; but it might well be a world where causal laws are at work.
- Causal laws are allowed to be context-dependent. Only the causal law will be established, and if the commitment to capacities is missing, no further inference can be drawn.
p.158 #1
- Cartwright’s principal claim is, not that the phenomena of economic life are governed by capacities, but rather that the methods of econometrics presuppose this.
- 논의 방향 제시
4.4. Beyond Modality
p.158 #2
- the concept of capacity involves more than just ascending levels of modality.
p.159 #1
- Carnap’s view of causation: causality is a concept not about the world, but about linguistic representations of world.
- 논리경험주의식 인과분석
: Claims of capacities function as metalinguistic summaries of facts about causal laws; causal laws must be recast as summaries of facts about non-causal laws; functional laws and probabilistic laws are to be eliminated, in favor of occurrent regularities.
p.159 #2
- 이 전략이 실패하는 이유
: the connection between causal laws and probabilistic laws
- Principle CC functions as a modal principle.
- constrains
p.160 #1
- 𝑪₁, ... , 𝑪ₙ₋₁에 𝑪ₙ 추가
- for some probabilistic structures, there will be no choice of a set of causal factors possible for a given effect, consistent with Principle CC.
p.160 #2
?
p.161 #1
Ch3에서 본 것
- to see causal laws as inference ticket from one probabilistic laws to another
- a concealed ceteris paribus condition for the inference ticket to obtain
- the constraints hold only ceteris paribus.
p.161 #2
- 또 다른 문제: the problem of the existence of theoretical entities
- Positivists tried to construe theories as summaries of laws about observables.
- Fine and van Frassen’s a valid inference ticket: the complete empirical adequacy
p.162 #1
- Sellars’s objection
- in fact a there are no laws about observables to summarize.
- Theories do not have unlimited applicability; the domain and limitations on the domain can be constructed only by already using the theory and the concept of theory.
p.162 #2
- difficulties for the purely modal view of capacities
(i) ceteris paribus conditions involve interactions;
(ii) There is the need to control for multiple.
- the most common reason for a capacity to fail to obtain in new situation is causal interaction.
- The property that carries the capacity interacts with some specific feature of the new situation, and the nature of the capacity is changed.
p.163 #1
- Mill thought causal interactions were the principal reason why chemistry was for less successful than physics.
- In mechanics, there is the laws of vector addition.
- In chemistry, the acid and the base neutralize each other.
p.163 #2
- Causal interactions are interactions of causal capacities, and they cannot be picked out unless capacities themselves can be recognized.
- non-circular account는?
p.164 #1
- the usual statistical characterization of an interaction
z = f(x, y) + u
- 기존 견해 설명
p.164 #2
- The claim that one can expect the relationship between X and z to be the same no matter what the level of y is, except in cases where x and y interact, means: you can expect the relationship to be the same except where it is different. (도움이 안 된다는 말)
p.165 #1
- 또 다른 해결책도 도움이 안 됨
p.166 #1
- the concepts of capacity and interaction
p.167 #1
- ‘the radical empiricist’ insists that there are just isolated empirical happening and nothing more.
- radical empirism is a doctrine either without ground, or grounded on mistaken premises.
p.167 #2
- There is now widespread agreement that Carnap’s project cannot work.
- Carnap’s project is to build the claims of science systematically from some acceptable empirical core.
- a strategy like van Frassen’s
p.168 #1
- the cases that have been studied are all cases of fitting low-level theories into models of high-level theories, and not cases which handle the ‘raw data’ itself.
- 이 전략이 간과하는 two crucial problems
- The first is the problem of how this ‘raw data’ is to be made to fit.
p.168 #2
- even at the lowest level, science never treats of the kind of datum that the radical empirist finds. Scienfici claims are tested, not against the empirist’s data but rather against ‘phenomena detected from them’.
e.g. James Bogen and James Woodward, Ian Hacking
- Scientific practice itself cannot be relied on to have already produced a model that contains both the raw data and the hypotheses.
p.169 #1
- The second problem is that it is easy to lose sight of the ceteris paribus conditions.
(두 문제는 focusing on the connection between lower- and higher-level theories)
- the need for ceteris paribus condition is felt most acutely when theory is brought to bear, not on a model, but on a real, concrete thing. For models are often constructed to fit the laws, with no need for ceteris paribus conditions.
p.169 #2
- ceteris paribus conditions must be introduced if one is stuck with the project of reducing causings and capacities.
- Cartwright advocates giving up that programme entirely and accepting that capacities and causings are real things in nature.
4.5. Mill in Defence of Capacities
p.170 #1
- Keynes maintained that economic phenomena were probably not atomistic. Mill believed that it was.
- Mill believed that the laws of political economy and the laws of mechanics alike are laws, not about what things do, but about what tendencies they have.
- Cartwright’s ‘capacity’ and Mill’s ‘tendency’ is synonymous.
p.170 #2
p.170 #3
- for Mill the opposite of a pure inductive method was not a kind of ‘a-priorism’, but rather a ‘mixed method of induction and ratiocination’.
- That means that the axioms are in no way arbitrary, but are rather to have two different kinds of support in experience:
(1) there must be a ‘direct induction as the basis of the whole’, and
(2) a kind of introspection or broad-based understanding of human nature.
p.171 #1
- Although Mill described his theories as deductive, it is not a structure that Cartwright would call deductive. For one cannot deduce even in principle what will occur in any future circumstance.
p.172 #1
4.6. Conclusion
(2015.11.27.)
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