13 November 2007

 

Philosophy of Biological and Cognitive Sciences

Matteo Mameli and David Papineau

Tuesdays 12-1.30 Lecture Room KCL Dept of Philosophy

KCL/LSE MSc in PHS

 

Reduction, Selection and Special Sciences

 

 

1.  There are good arguments for physicalism.

2.  A strong version of physicalism is classical type reduction.  Special types can be equated with physical types (bridge laws) and special laws therefore explained i.t.o. physical laws.  (NB this is a synchronic not diachronic thesis.)

                       S1      ->        S2x                                   

                       ║                     ║

                        P1      ->        P2     

3.  Many physicalists go for the weaker non-reductive physicalism.  Special types are multiply realized and laws are not physically explicable.  Fodor’s ‘Special Sciences’.

        S1------------------- > S2 

↑   ↑   ↑   ↑                    ↑     ↑   ↑

P1 P2 P3 P4                         Q1 Q2 Q3

↓   ↓                              ↑     ↑

---------------------- >

      ---------------------- >

4.  Are special laws consistent with multiple realizability?  Brussells sprouts example.  This problem doesn’t arise just because there are some physical differences between the realizers (eg an increase in temperature can be many different molecular movements).  That’s consistent with type reduction.  It arises when there is no physical commonality that can explain why all the realizers produce the same effect—that is, when the possible realizers are too disparate to form a physical kind.

5. Kim (1992):  if the realizations don’t form a kind, then they can’t feature in laws.  Alternatively, if the realizations do form a kind, then this will be type reduction after all.  Fodor (1997) says this begs the question—special kinds aren’t physical kinds—they enter into special not physical laws.  Still, contra Fodor, don’t special kinds characteristically also enter into laws involving physical kinds?

6.  This argues that either there’s reduction, or there are no laws.  Can run this argument both ways—against laws, or for reduction. 

6.  How come the heating always goes off at c. 20C?  Similarly, maybe natural selection has ensured that eg different organisms will all have some mechanism that responds to bodily damage with avoidance behaviour.  This doesn’t require that it’s the same mechanism in different cases.  (Cf Papineau, 1993.)  So maybe we will have non-reduced special laws in just those areas which have been subject to some sort of design/selection processes.

7.  Note, however, that this selectional explanation does not vindicate non-reduced sciences, in the sense of giving us special kinds that will enter into lots of laws.  Thus, we wouldn’t expect generalizations about pain reaction times, anaesthetics, etc to hold good across different species.

8.  Where does this leave psychological laws?  There will be some type commonalities, eg the pain mechanism.  And there will be an awful lot of common selection pressures in learning.

 

Readings

 

Fodor, J. (1974): "Special sciences and the disunity of science as a working hypothesis", Synthese, 28, pp. 77-115.  Reprinted in his Representations

 

Kitcher, P. 1984 “1953 And All That: A Tale of Two Sciences” Philosophical Review 93

 

Kim, J. 1992 "Multiple Realizability and the Metaphysics of Reduction" Philosophy and Phenomenological Research 52, 1-26. Reprinted in his Supervenience and Mind, Cambridge: Cambridge University Press, 1993, 309-336

 

Fodor, Jerry (1997). “Special Sciences: Still Autonomous After All These Years” in Tomberlin, James (ed.) Philosophical Perspectives 11: Mind, Causation, and World Boston: Blackwell

 

Block, N. (1997) “Anti-Reductionism Slaps Back”

 

Papineau, D. 1993 Philosophical Naturalism Ch 2 Blackwell

 

Rosenberg, A. 2001 “On multiple realization and special sciences”, Journal of Philosophy 98