Reductionism (2)

[Lycidas at worldnet.att.net]

 " Traditionally, the subject matter of empirical science is
 grouped into areas of decreasing scope.  Physics is thought
of as
 having the broadest scope because it deals with the
physical
 properties  of all bodies and all bodies have physical
properties.
 Chemistry is  viewed as being only slightly less basic,
because all
 material  substances also have chemical properties; 
however,
 chemical properties  are explained by reference to physical
 properties, and physics and  chemistry become fused at the
level of
 their most fundamental axioms.   Biology is considered to
have a
 more limited scope than physics and  chemistry because it
concerns
 only those physical objects which are  also alive.  All
living
 organisms are physical objects, but not all  physical
objects are
 alive.  Psychology is of even more limited scope,  because
it deals
 only with those living creatures capable of sensation,  
Sociology
 in turn is of even narrower scope, dealing only with 
sentient
 beings organized into societies.
      Philosophers and scientists have used the term
"reduction" in
 a  variety of ways.  Given the above analysis of scientific
 theories and  the organization of the subject matter of
science
 into the usual  hierarchy, three senses of "reduction" can
be
 distinguished with some  clarity - epistemological
reduction,
 physical reduction, and  theoretical reduction. 
Epistemological
 reduction concerns the proper  relation between scientific
theories
 themselves.
      The goal of epistemological reduction is the
elimination of
 any  reference to theoretical entities in scientific
theories.
 Instead,  scientific theories are to be reformulated so
that they
 refer only to  the objects of our knowledge.  There is some
 disagreement among  epistemological reductionists over the
nature
 of these objects.    According to one version of
epistemological
 reduction, all scientific  statements are to be
reformulated in
 terms of gross physical objects,  usually measuring
instruments
 like yardsticks and galvanometers.   Another version
specifies
 their reformulation in terms of sense data  like "red patch
now."
 The appeal of epistemological reduction stems  from the
empiricist
 claim that all empirical knowledge comes from sense 
experience;
 hence, it should be reducible to it.  In point of fact, 
neither of
 these versions of epistemological reduction has met with 
much
 success.  Nor do the issues raised by epistemological
reduction
 have much to do with biology or vice versa.  Accordingly,
this
 sense of  reduction will be all but ignored in what
follows.
      In physical reduction, systems at one level are
analyzed into
 their component parts and the behavior of these
higher-level
 systems  are explained in terms of the properties,
behaviors and
 arrangements  of these parts.  The stock example of
reduction to be
 found in the  philosophical literature is the explanation
of the
 gross properties of  gases (like temperature) in terms of
the
 movements of the molecules  that make them up.  Similarly,
the
 molecular geneticists are attempting  to explain the
behavior of
 genes in molecular terms.  In theory  reduction the axioms
of one
 theory are derived as theorems from the  axioms of another
theory,
 and the derived theory is said to be reduced  to the
original
 theory.  Again, the stock example of such a reduction  is
the
 derivation of classical thermodynamics from statistical 
mechanics
 by identifying the temperature of a gas with the mean
 translational kinetic energy of the molecules which make it
up.
      Given the preceding hierarchy of subject matters of
science,
 the  results of physical reduction and theory reduction
tend to
 coincide.   Both with respect to the scope of the relevant
theories
 and the level  of physical analysis, physics is basic. 
Physics
 deals with the  physical properties of systems from the
most
 organized beings to the  simplest subatomic particles,
whereas
 biology, for example, deals with  the properties of only
highly
 organized beings.  Scientific theories  are formulated at
all such
 levels of analysis from the universe to  evolving species
to
 subatomic particles.  A reduction is termed  intralevel if
both
 theories concerned refer to phenomena at the same  level of
 analysis and belong to the same traditional area of
science.   If
 either of these conditions is not met, then the reduction
is
 termed  interlevel.  Hence, the reduction of thermodynamics
to
 statistical  mechanics is intralevel in the sense that both
 theories are physical  theories, but interlevel in the
sense that
 the reducing theory concerns  lower-level phenomena than
the theory
 being reduced."                               David Hull,
                           _Philosophy of Biological
Science_
                          (Foundations of Philosophy
Series),
                                1974, pp. 3-4

 reductionism
 noun
 (1) An attempt or a tendency to explain complex phenomena
or
 structures by relatively simple principles, as by asserting
that
 life processes or mental acts are instances of chemical and
 physical laws: "Our educational system has had a dangerous
 predilection for reductionism--an addiction to the primary,
the
 elementary" Source: Frederick Turner

 reductionism
 noun
 (1) An attempt or a tendency to explain complex phenomena
or
 structures by relatively simple principles, as by asserting
that
 life processes or mental acts are instances of chemical and
 physical laws: "Our educational system has had a dangerous
 predilection for reductionism--an addiction to the primary,
the
 elementary"