Diederik Aerts and Fritz Rohrlich
Center Leo Apostel,
Brussels Free University,
Department of Physics,
1160 Brussels, Belgium.
To avoid misunderstanding, it is desirable to specify here a meaning of reduc-
tion which we shall not consider in the following. 'Reduction' has been used
(especially by logical positivists) to denote the claim that a scientific theory can
be expressed entirely in terms of observation statements, or, weaker, that all
theoretical terms of a theory can be so expressed. We make no such claims and
shall understand by 'reduction' the following three types.
(1) Logical reduction
(2) Theory reduction (sometimes called 'semantic reduction')