Explanatory Fictions and Fictional Explanations Sorin Bangu Univ. - - PowerPoint PPT Presentation
Explanatory Fictions and Fictional Explanations Sorin Bangu Univ. of Bergen Sorin.Bangu@fof.uib.no Can fictions explain? - question of perennial interest one of the main and most controversial roles that fictional assumptions may play
“one of the main and most controversial roles that fictional assumptions may play” (Suarez 2009, 7) Fictionalism
scientists seem fine with a ‘yes’ answer
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“one of the main and most controversial roles that fictional assumptions may play” (Suarez 2009, 7) Fictionalism
scientists seem fine with a ‘yes’ answer
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Cautious ‘yes’: in what circumstances (new) Account: two steps
fictions fictional explanations (genuine) explanations role in should be accepted as
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If SC doesn’t exist, then how is it that there are gifts under the three? Explanation :: Understanding
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If vortices don’t exist, then how is it that the Moon moves? Explanation :: Understanding
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding total falsehoods: gross ‘cancellation effect’ Russell syllogism bread is stone / milk stone / milk is nourishing bread is nourishing
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding idealizations / approximations partial falsehoods: subtle ‘cancellation effect’ Scientific modeling false / idealized explanans true explanandum total falsehoods: gross ‘cancellation effect’ Russell syllogism bread is stone / milk stone / milk is nourishing bread is nourishing
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding idealizations / approximations partial falsehoods: subtle ‘cancellation effect’ Scientific modeling false / idealized explanans true explanandum total falsehoods: gross ‘cancellation effect’ Russell syllogism bread is stone / milk stone / milk is nourishing bread is nourishing
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding idealizations / approximations partial falsehoods: subtle ‘cancellation effect’ Scientific modeling false / idealized explanans true explanandum total falsehoods: gross ‘cancellation effect’ Russell syllogism bread is stone / milk stone / milk is nourishing bread is nourishing ‘Concerned’ v. ‘unconcerned’ with the truth [Winsberg 2009]
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If the EXPLANANS are false / fictions, then how is it that the EXPLANANDUM holds / is true? Explanation :: Understanding idealizations / approximations partial falsehoods: subtle ‘cancellation effect’ Scientific modeling false / idealized explanans true explanandum total falsehoods: gross ‘cancellation effect’ Russell syllogism bread is stone / milk stone / milk is nourishing bread is nourishing Hempel: no explanation Salmon: no explanation ‘Concerned’ v. ‘unconcerned’ with the truth [Winsberg 2009]
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Explananas (L + IC) Explanandum Four conditions for an explanation …
adequacy” = the sentences constituting the explanans must be true (1965, 248) …
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Explananas (L + IC) Explanandum Four conditions for an explanation …
adequacy” = the sentences constituting the explanans must be true (1965, 248) …
Woodward, Strevens, etc.
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Solution: Fictional content is eliminable dispensable, etc.
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Bogen, J., and J. Woodward (1988) Saving the phenomena The Philosophical Review 97: 303-352.
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Bogen, J., and J. Woodward (1988) Saving the phenomena The Philosophical Review 97: 303-352.
Data
phenomena Phenomena
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Monopoly principle ‘buy fictional property with fictional money’
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fictional explanation
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fictional explanation acceptable when no genuine explanation exists = one in which the explananda are phenomena, not ‘phenomena’
Fictionalist principle ‘fictions in explananda allow fictions in the explanans’
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the property of ‘changing state’: liquid vapor (gas) ice (solid)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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the property of ‘changing state’: liquid vapor (gas) ice (solid)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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“So, here is a problem for the theoretical physicist: prove that as you raise or lower the temperature of water you have phase transitions to water vapor or to ice. Now, that’s a tall order! We are far from having such a proof. In fact there is not a single type of atom or molecule for which we can mathematically prove that it will crystallize at low temperature. These problems are just too hard for us.” (D. Ruelle 1991: 123-4)
the property of ‘changing state’: liquid vapor (gas) ice (solid)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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1. Functionalize
More precisely:
varies discontinuously (Zemansky 1968, 347)
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H = enthalpy of the system = total energy = internal energy + pV
1. Functionalize
More precisely:
varies discontinuously (Zemansky 1968, 347)
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H = enthalpy of the system = total energy = internal energy + pV T = temperature
S = entropy of the system = system's ability to do work
1. Functionalize
More precisely:
its derivative (tangent) varies discontinuously (Zemansky 1968, 347)
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(Stanley 1971, 31)
1. Functionalize
Explanans: water molecules + Statistical Mechanics (QSM)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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1. Functionalize
Explanans: water molecules + Statistical Mechanics (QSM)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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r Er
1. Functionalize
Explanans: water molecules + Statistical Mechanics (QSM)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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r Er
G can’t have a singularity! Impossible to find one in principle (mathematical result) Reduction is blocked at step 2: realizers + theory Boiling = case of emergence not captured in the Kim-Chalmers model
step 1
1. Functionalize
Explanans: water molecules + Statistical Mechanics (QSM)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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r Er
G can’t have a singularity! Impossible to find one in principle (mathematical result) G depends on Z, so if G is to have singularities, Z has to have singularities. But Z can’t have singularities (is analytic). Z is a finite sum of analytic functions (not having singularities), and any finite sum of analytic functions is analytic (no singularities) So G can’t have singularities b.c. of Z.
1. Functionalize
Explanans: water molecules + Statistical Mechanics (QSM)
Water (H20) molecules Statistical Mechanics (QSM) “When all of this is in, we are entitled to the claim that [boiling] has been reduced to the [behavior of molecules].”
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r Er
G can’t have a singularity! Impossible to find one in principle (mathematical result) G depends on Z, so if G is to have singularities, Z has to have singularities. But Z can’t have singularities (is analytic). Z is a finite sum of analytic functions (not having singularities), and any finite sum of analytic functions is analytic (no singularities) So G can’t have singularities b.c. of Z (Kadanoff 2000) “So, here is a problem for the theoretical physicist: prove that as you raise or lower the temperature of water you have phase transitions to water vapor or to ice. Now, that’s a tall order! We are far from having such a proof. In fact there is not a single type of atom or molecule for which we can mathematically prove that it will crystallize at low temperature. These problems are just too hard for us.” (D. Ruelle 1991: 123-4)
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N = number of molecules V = volume “The existence of a phase transition requires an infinite system. No phase transitions occur in systems with a finite number of degrees of freedom.” (Kadanoff 2000, 238)
Explanandum
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“The existence of phase transitions shows that we have to be careful when we adopt a reductionist approach. Phase transitions correspond to emerging properties.” (Prigogine 1997, 45)
whether the ‘corners’ which bound [phase transitions] regions are sharp or round” (Liu 2001, 328)
(Liu 1999, S104)
the specific sense of Bogen and Woodward. “ (Bangu 2009, 49)
Explanandum
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“The existence of phase transitions shows that we have to be careful when we adopt a reductionist approach. Phase transitions correspond to emerging properties.” (Prigogine 1997, 45)
whether the ‘corners’ which bound [phase transitions] regions are sharp or round” (Liu 2001, 328)
(Liu 1999, S104)
the specific sense of Bogen and Woodward. “ (Bangu 2009, 499)
Explanandum
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“The existence of phase transitions shows that we have to be careful when we adopt a reductionist approach. Phase transitions correspond to emerging properties.” (Prigogine 1997, 45)
whether the ‘corners’ which bound [phase transitions] regions are sharp or round” (Liu 2001, 328)
(Liu 1999, S104)
the specific sense of Bogen and Woodward. “ (Bangu 2009, 499)
Explanandum
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“The existence of phase transitions shows that we have to be careful when we adopt a reductionist approach. Phase transitions correspond to emerging properties.” (Prigogine 1997, 45)
whether the ‘corners’ which bound [phase transitions] regions are sharp or round” (Liu 2001, 328)
(Liu 1999, S104)
the specific sense of Bogen and Woodward. “ (Bangu 2009, 499)
Explanandum
fictional explanation acceptable when no genuine explanation exists = one in which the explananda are phenomena, not ‘phenomena’
Fictionalist principle ‘fictions in explananda allow fictions in the explanans’
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fictional explanation acceptable when no genuine explanation exists = one in which the explananda are phenomena, not ‘phenomena’ no explanation exists in which the explanandum = phase transition (a real process!) is not represented as a singularity (and the explanans don’t involve an infinite system)
Fictionalist principle ‘fictions in explananda allow fictions in the explanans’
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