Date: Mon, 5 Aug 1996 15:38:59 -0600
From: Hans Ehrbar <ehrbar-AT-marx.econ.utah.edu>
Subject: rts2-12


24 A Realist Theory of Sciencen

2. THREE TRADITIONS IN THE PHILOSOPHY OF SCIENCE   

Viewed historically, three broad positions in the
philosophy of science may be distinguished.  According to
the first, that of *classical empiricism*, represented by
Hume and his heirs, the ultimate objects of knowledge are
atomistic events.  Such events constitute given facts and
their conjunctions exhaust the objective content of our
idea of natural necessity.  Knowledge and the world may
be viewed as surfaces whose points are in isomorphic

Philosophy and Scientific Realism 25

correspondence or, in the case of phenomenalism, actually
fused.  On this conception, science is conceived as a
kind of automatic or behavioural response to the stimulus
of given facts and their conjunctions.  Even if, as in
logical empiricism, such a behaviourism is rejected as an
account of the genesis of scientific knowledge, its valid
content can still in principle be reduced to such facts
and their conjunctions.  Thus science becomes a kind of
epiphenomenon of nature.

     The second position received its classical though
static formulation in Kant's *transcendental idealism*,
but it is susceptible of updated and dynamized
variations.  According to it, the objects of scientific
knowledge are models, ideals of natural order etc.  Such
objects are artificial constructs and though they may be
independent of particular men, they are not independent
of men or human activity in general.  On this conception,
a constant conjunction of events is insufficient, though
it is still necessary, for the attribution of natural
necessity.  Knowledge is seen as a structure rather than
a surface.  But the natural world becomes a construction
of the human mind or, in its modern versions, of the
scientific community.

     The third position, which is advanced here, may be
characterized as *transcendental realism*.  It regards the
objects of knowledge as the structures and mechanisms
that generate phenomena; and the knowledge as produced in
the social activity of science.  These objects are
neither phenomena (empiricism) nor human constructs
imposed upon the phenomena (idealism), but real
structures which endure and operate independently of our
knowledge, our experience and the conditions which allow
us access to them.  Against empiricism, the objects of
knowledge are structures, not events; against idealism,
they are intransitive (in the sense defined).  On this
conception, a constant conjunction of events is no more a
necessary than it is a sufficient condition for the
assumption of the operation of a causal law.  According
to this view, both knowledge and the world are
structured, both are differentiated and changing; the
latter exists independently of the former (though not our
knowledge of this fact); and experiences and the things
and causal laws to which it affords us access are
normally out of phase with one another.  On this view,
science is not an epiphenomenon of nature, nor is nature
a product of man.

26 A Realist Theory of Science


     A word of caution is necessary here.  In outlining
these positions, I am not offering them as a complete
typology, but only as one which will be of some
significance in illuminating current issues in the
philosophy of science.  Thus I am not concerned with
rationalism as such, or absolute idealism.  Moreover,
few, if any, modern philosophers of science could be
unambiguously located under one of these banners.  Nagel
for example stands somewhere along the continuum between
Humean empiricism and neo-Kantianism; Sellars nearer the
position characterized here as transcendental realist;
and so on.  One could say of such philosophers that they
combine, and when successful in an original way
synthesize, aspects of those philosophical limits whose
study we are undertaking.  It is my intention here, in
working out the implications of a full and consistent
realism, to describe such a limit; in rather the way Hume
did.  As an intellectual exercise alone this would be
rewarding, but I believe, and hope to show, that it is
also the only postion that can do justice to science.

     Transcendental realism must be distinguished from,
and is in direct opposition to, *empirical realism*.
This is a doctrine to which both classical empiricism and
transcendental idealism subscribe.  My reasons for
rejecting it will be elaborated in a moment.  `Realism'
is normally associated by philosophers with positions in
the theory of perception or the theory of universals.  In
the former case the real entity concerned is some
particular object of perception; in the latter case some
general feature or property of the world.  The `real
entities' the transcendental realist is concerned with
are the objects of scientific discovery and
investigation, such as causal laws.  Realism about such
entities will be seen to entail particular realist
positions in the theory of perception and universals, but
not to be reducible to them.

     Only transcendental realism, I will argue, can
sustain the idea of a law-governed world independent of
man; and it is this concept, I will argue, that is
necessary to understand science.

     Classical empiricism can sustain neither transitive
nor intransitive dimensions; so that it fails both the
criteria of adequacy (1)' and (2)' advanced on page 24
above.  Moreover in its most consistent forms it involves
both solipsism and phenomenalism; so that neither (1) nor
(2) can be upheld.  In particular

Philosophy and Scientific Realism 27

not even the idea of the independence of the event from
the experience that grounds it, i.e. the intransitivity
of events, can be sustained; and, in the last instance,
events must be analysed as sensations or in terms of what
is epistemologically equivalent, viz. human operations.

     Transcendental idealism attempts to uphold the
objectivity (intersubjectivity) of facts, i.e. (1).  And,
if given a dynamic gloss, it can allow a transitive
dimensions and satisfy criterion (1)'; so that, in this
respect, it is an improvement on empiricism.  According
to such a dynamized transcendental idealism knowledge is
given structure by a sequence of models, rather than a
fixed set of a priori rules.  However in neither its
static nor its dynamic form can it sustain the
intransitive dimension.  For in both cases the objects of
which knowledge is obtained do not exist independently of
human activity in general.  And if there are things which
do (things-in-themselves), no scientific knowledge of
them can be obtained.

     Both transcendental realism and transcendental
idealism reject the empiricist account of science,
according to which its valid content is exhausted by
atomistic facts and their conjunctions.  Both agree that
there could be no knowledge without the social activity
of science.  They disagree over whether in this case
there would be no nature also.  Transcendental realism
argues that it is necessary to assume for the
intelligibility of science that the order discovered in
nature exists independently of men, i.e. of human
activity in general.  Transcendental idealism maintains
that this order is actually imposed by men in their
cognitive activity.  Their differences should thus be
clear.  According to transcendental realism, if there
were no science there would still be a nature, and it is
this nature which is investigated by science.  Whatever
is discovered in nature must be expressed in thought, but
the structures and constitutions and causal laws
discovered in nature do not depend upon thought.
Moreover, the transcendental realist argues, this is not
just a dogmatic metaphysical belief; but rather a
philosophical position presupposed by key aspects of the
social activity of science, whose intelligibility the
transcendental idealist cannot thus, anymore than the
empiricist, sustain.

     Neither classical empiricism nor transcendental
idealism can sustain the idea of the independent
existence and action of the

28 A Realist Theory of Science

causal structures and things investigated and discovered
by science.  It is in their shared ontology that the
source of this common incapacity lies.  For although
transcendental idealism rejects the empiricist account of
science, it tacitly takes over the empiricist account of
being.  This ontological legacy is expressed most
succintly in its commitment to empirical realism, and
thus to the concept of the `*empirical world*'.  For the
transcendental realist this concept embodies a sequence
of related philosophical mistakes.  The first consists in
the use of the category of experience to define the
world.  This involves giving what is in effect a
particular epistemological concept a general ontological
function.  The second consists in the view that it's
being experienced or experienciable is an essential
property of the world; whereas it is more correctly
conceived as an accidental property of some things,
albeit one which can, in special circumstances, be of
great significance for science.  The third thus consists
in the neglect of the (socially produced) circumstances
under which experience is in fact epistemically
significant in science.

     If the bounds of the real and the empirical are
co-extensive then of course any `surplus-element' which
the transcendental idealist finds in the analysis of
law-like statements cannot reflect a real difference
between necessary and accidental sequences of events.  It
merely reflects a difference in men's attitude to them.
Saying that light travels in straight lines ceases then
to express a proposition about the world; it expresses
instead a proposition about the way men understand it.
Structure becomes a function of human needs; it is denied
a place in the world of things.  But just because of
this, I shall argue, the transcendental idealist cannot
adequately describe the principles according to which our
theories are constructed and empirically tested; so that
the rationality of the transitive process of science, in
which our knowledge of the world is continually extended
and corrected, cannot be sustained.

     To say that the weaknesses of both the empiricist
and idealist traditions lie in their commitment to
empirical realism is of course to commit oneself to the
impossibility of ontological neutrality in an account of
science; and thus to the impossibility of avoiding
ontological questions in the philosophy of science.  The
sense in which every account of science presupposes an
ontology is the sense in which it presupposes a schematic

Philosophy and Scientific Realism 29

answer to the question of what the world must be like for
science to be possible.  Thus suppose a philosopher
holds, as both empiricists and transcendental idealists
do, that a constant conjunction of events apprehended in
sense-experience is at least a necessary condition for
the ascription of a causal law and that it is an
essential part of the job of science to discover them.
Such a philosopher is then committed to the belief that,
given that science occurs, there are such conjunctions.
As Mill put it, that `there are such things in nature as
parallel cases; that what happens once will, under a
sufficient degree of similarity of circumstance, happen
again'.7

     There are two important points to register about
such ontological beliefs and commitments.  The first is
that they should only be interpreted hypothetically,
viz. as entailing what must be the case for science to be
possible; on which interpretation it is a contingent fact
that the world is such that science can occur.  It is
only in this relative or conditional sense that an
account of science presupposes an ontology.  The status
of propositions in ontology may thus be described by the
following formula: It is not necessary that science
occurs.  But given that it does, it is necessary that the
world is a certain way.  It is contingent that the world
is such that science is possible.  And, given that it is
possible, it is contingent upon the satisfaction of
certain social conditions that science in fact occurs.
But given that science does or could occur, the world
*must* be a certain way.  Thus, the transcendental realist
asserts, that the world is structured and differentiated
can be established by philosophical argument; though the
particular structures it contains and the ways in which
it is differentiated are matters for substantive
scientific investigation.  The necessity for categorical
distinctions between structures and events and between
open systems and closed are indices of the stratification
and differentiation of the world, i.e. of the
transcendental realist philosophical ontology.  These
distinctions are presupposed, it will be shown, by the
intelligibility of experimental activity.  Whenever there
is any danger of confusion between an `ontology' in the
sense of the kind of world presupposed by a philosophical
account of science and in the sense of the particular
entities and processes postulated by some

 7 J. S. Mill, A System of Logic, Bk. III, Chap. 3, Sect. 1.

30 A Realist Theory of Science

substantive scientific theory I shall explicitly
distinguish between a philosophical and a scientific
ontology.

     The second point to stress is that propositions in
ontology cannot be established independently of an
account of science.  On the contrary, they can only be
established by reference to such an account, or at least
to an account of certain scientific activities.  However,
it will be contended that this essential order of
analysis, viz. science --> being, *reverses* the real
nature of dependency (or, we could say, the real burden
of contingency).  For it is not the fact that science
occurs that gives the world a structure such that it can
be known by men.  Rather, it is the fact that the world
has such a structure that makes science, whether or not
it actually occurs, possible.  That is to say, it is not
the character of science that imposes a determinate
pattern or order on the world; but the order of the world
that, under certain determinate conditions, makes
possible the cluster of activities we call `science'.  It
does not follow from the fact that the nature of the
world can only be *known* from (a study of) science, that
its nature is *determined* by (the structure of) science.
Propositions in ontology, i.e. about being, can only be
established by reference to science.  But this does not
mean that they are disguised, veiled or otherwise
elliptical propositions about science.  What I shall
characterize in a moment as the `*epistemic fallacy*'
consists in assuming that, or arguing as if, they are.