Erschienen in Ausgabe: No. 21 (1/2005) | Letzte Änderung: 27.01.09 |
Is a naturalised epistemology bound to leave unanswered some important epistemological questions?
von Lukas Graf
For Quine epistemology as it is
traditionally approached in philosophy is mistaken because it is
based on the untenable concept of foundationalism. However, Quine’s
contribution to epistemology is not merely a destructive one; he
comes up with a new theory. Anyone assessing this theory, naturalised
epistemology, ultimately wants to know whether it provides an answer
to the central questions of epistemology. In this paper it is
discussed whether naturalised epistemology is bound to leave
some of these questions unanswered.
The essay starts with a definition
of naturalised epistemology, followed by an explanation of the
relevant epistemological questions. Then the two key questions in
this context, the first relating to the existence of the external
world and to scepticism and the second to the justification of
beliefs, are examined more closely.
Central
to naturalised epistemology is the claim that epistemology is a
branch of psychology. ‘The stimulation of his sensory receptors
is all the evidence anybody has had to go on, ultimately, in arriving
at his picture of the world’1
and it is psychology which studies how humans construct their beliefs
about the world given the sensory stimuli they receive. In the same
way, the ‘new’ epistemologist seeks to explain how
theoretical output is caused by sensory input; he studies the causal
relationship between meagre input and torrential output. That is to
say, epistemology is conducted in a scientific manner, and hence
naturalised.
In
Quine’s opinion epistemology is a discipline of science, where
science can be said to be the more successful enterprise than
philosophy, exemplified by the phenomenon that, with developments in
traditional epistemology, things are becoming more rather than less
complicated. In the new setting philosophy and science differ only in
degree, not in kind. Foundationalism is replaced by naturalised
epistemology and the foundational approach to epistemology merges
into a scientific one.2
Quine brings out the difference between naturalised and traditional
epistemology in the following way:
‘The old epistemology aspired to contain, in a sense, natural science; it would construct it somehow from sense data. Epistemology in its new setting, conversely, is contained in natural science, as a chapter of psychology.’3
Hence, it can be said that traditional epistemology is pursued a priori whereas naturalised epistemology utilizes empirical investigation. However, if there is an area of epistemological investigation which can only be approached a priori, then naturalised epistemology is unable to answer some important epistemological questions:
‘If the opponents of naturalism are correct, then there are legitimate epistemological questions which are susceptible to a priori investigation; these questions, they would argue, are rightly regarded as purely philosophical.’4
On the assumption that the questions
that a traditional epistemologist asks are vital to any theory of
knowledge, it follows that an important epistemological question
which naturalised epistemology is bound to leave unanswered is a
question that is important to the traditional epistemologist but
cannot be answered by a naturalist in epistemology.
An epistemological question to be
considered in this connection is a question that relates to
scepticism and the existence of the external world. Traditional
epistemology is concerned with scepticism and asks whether there is
an external world and what it is like.
In
attempting to answer this question the traditional epistemologist is
not making use of any scientific findings. Conversely, Quine’s
claim that epistemology is contained in natural science implies that
naturalised epistemology does make use of scientific findings.
For
a traditional epistemologist the existence of the resources of
science is questioned in exactly the same way as everything else and,
hence, he does not allow for a presupposition of the existence of the
resources of science in order to use them as evidence for other
things. Quine puts it in the following way: ‘The old tendency
was due to the drive to base science on something firmer and prior in
the subject’s experience.’5
As
a consequence of its making use of psychology in its epistemological
enterprise, a naturalist in epistemology has to make the assumption
that there is an external world, and he ignores scepticism. However,
an epistemologist cannot disregard the question as to whether
the grounds of science can be validated. It would clearly be circular
reasoning if the epistemologist used science in his attempt to
validate science. In regard to this problem Quine holds that ‘such
scruples against circularity have little point once we have stopped
dreaming of deducing science from observations.’6
However, as a consequence, the naturalist in epistemology can never
arrive at a valid answer to the question whether the grounds of
science can be validated.7
Naturalised epistemology presupposes science in order to solve the
problem of knowledge; naturalised epistemology is built on this very
presupposition. In making the presupposition about the existence of
the resources of science and with that a presupposition about the
external world, a naturalist in epistemology cannot possibly answer
the epistemological question about the existence of the external
world. The naturalist in epistemology assumes the existence of
the external world.
Moreover,
naturalised epistemology does not rule out the possibility that our
view of the world around us is an illusion.8
Naturalised epistemology locates epistemology within natural science,
and a scientist takes no notice of scepticism because otherwise he
could not make much sense of his scientific work. Accordingly, a
naturalist in epistemology cannot accept the sceptic’s
wholesale doubt and, in contrast to the traditional epistemologist,
ignores scepticism.
However, nothing prevents the
naturalist in epistemology from supplementing his theory with
additional independent philosophical arguments designed to refute
scepticism and prove his assumption that there is an external world.
And, indeed, Quine deploys such arguments which are perfectly
compatible with naturalised epistemology.
One of these arguments points out
that if scepticism is true, everything could turn out to be false and
hence everything could be an illusion. Quine argues that if
everything were an illusion, that is to say in the absence of any
reality, there would be nothing to contrast illusion with.
Furthermore, given the lack of such a contrast, the notion of an
‘illusion’ would, so to speak, cease to exist. Hence,
scepticism is self-refuting.
Another argument Quine refers to is
the ‘best explanation’ argument, according to which
belief in the external world is justified because it provides the
best explanation for the sensory data stimulating us. Moreover, to a
certain extent at least some of our beliefs about the world are
ensured as accurate because we are still alive; our beliefs are
justified in a somewhat evolutionary sense. If we were constantly
deceived, we would not be able to survive; for example it would be
impossible to tell which food was poisonous if our beliefs did not to
a certain extent match reality. Scepticism appears to be mistaken
because beliefs seem to ‘work’. According to Quine, the
existence of a persisting and rule-bound external world is ensured
because it is the most plausible economic explanation which makes
predictions about the future possible and allows scientists to do
their job.
So the assumptions which underlie
naturalised epistemology can be backed up by independent arguments,
but as long as such arguments are not incorporated into the concept
of naturalised epistemology, naturalised epistemology on its own does
not address and hence does not answer traditionally important
epistemological questions in relation to the existence of the
external world and scepticism.
A second epistemological question to
be considered relates to the justification of beliefs. The
traditional epistemologist wants to know what the justifications are
for our beliefs. He wants to know what good reasons for holding a
belief are, and therefore asks a normative question.
A crucial difference between
naturalised and traditional epistemology is that the data for
naturalised epistemology are physical stimuli, whereas the data for
traditional epistemology are conscious states. In the concept of
naturalised epistemology consciousness seems to be excluded; being a
conscious being is not a necessary condition for being a knowing
being.
A naturalist in epistemology is
interested in the route of causation which brings about the
transformation from meagre input to torrential output; he isn’t
interested in a justificatory route. He is paying attention to the
causal relationship between sensory input and the belief that is
formed on the basis of this input. He asks what the causes for our
beliefs are. He seeks an answer to the question about why we believe
what we believe.
Whether
a belief is justified or not depends on whether the physical stimulus
causing the belief is justified. Naturalised epistemology is not in a
position to detect this. An unjustified physical stimulus is
processed in exactly the same way as a justified one. From within
naturalised epistemology it is irrelevant whether a belief is
justified or not. The traditional epistemological question of what
justifies a belief is an independent subject matter from the
perspective of a proponent of naturalised epistemology.9
To
summarize, naturalised epistemology is concerned with the causal
explanation of beliefs, and traditional epistemology with their
justification.10
It seems as if naturalised epistemology is bound to leave unanswered
the important traditional epistemological question of what justifies
a belief. At first sight it seems as if Quine abandons norms
altogether.
However, the statement that
naturalised epistemology has nothing to contribute to and hence is
not concerned with the question of whether a belief is justified can
be challenged. Quine holds that the scientific approach is normative
and argues that the normative is naturalised, not dropped. The
normative can be located within the scientist’s factual realm;
a normative question can be answered by appealing to factual issues,
for example to facts about causation and probability. For example if
we assume that a belief is caused by other beliefs and its truth
value depends on the truth value of these causing beliefs, then a
scientist can apply scientific concepts of causation and probability
to investigate whether we ought to hold this belief. That is to say
if a belief is produced by a reliable method, then it is entirely
possible for a scientist to approach normative questions about this
belief. In this case a scientist can, without ‘missing’
non-naturalistic concepts of justification, make normative
judgements, because the normative can be naturalised.
From this perspective it seems as if
it is necessary to modify the position, reached in the previous
paragraph, that naturalised epistemology cannot account for normative
epistemological questions. At least on the assumption that beliefs
are produced by a reliable method it seems as if naturalised
epistemology is not bound to leave unanswered the question about the
justification of beliefs.
What
important epistemological questions actually are is an issue which
depends on the very nature of epistemological inquiry.11
The concepts of naturalised and traditional epistemology are
dissimilar; questions each can pose cannot be the same and,
consequently, the set of answers each can provide is different.
Critics like Rorty hold that ‘Quine dissolves a dilemma only by
changing the motives of inquiry.’12
Barry Stroud argues that it is important to distinguish Quine’s
epistemological project from traditional epistemological concerns.13
According to some of these critics
it might even be doubted whether naturalised epistemology should be
called epistemology at all.
It was said earlier that naturalised
epistemology is unable to answer some important epistemological
questions if there was an area of epistemological investigation
which could only be approached in the traditional way. With regard to
investigations into the justification of beliefs, naturalised
epistemology can provide us with an answer on the assumption that it
is possible to naturalise the normative. However, in relation to the
role of scepticism and to questions with regard to the existence of
the external world, naturalised epistemology itself (that is to say
without reference to other independent philosophical arguments) is
not equipped to answer important epistemological questions. The
epistemological questions naturalised epistemology cannot answer are
the very questions which query the assumptions naturalized
epistemology is built on. Hence it can be concluded that there are
some epistemological questions which naturalised epistemology is
bound to leave unanswered.
Craig,
E. (Ed.): Routledge Encyclopaedia of Philosophy; volume 3,
Routledge, 1998
Everitt,
N.; Fisher, A.: Modern Epistemology, A New Introduction;
McGraw-Hill Inc., 1995
Koppelberg,
D.: Why and how to naturalise epistemology; in Barret, R. B.;
Gibson, R. F. (Eds.): Perspectives on Quine; Basil Blackwell, 1990
Kornblith,
H.: In Defence of a Naturalised Epistemology; in Greco, J;
Sosa, E. (Eds.): The Blackwell Guide to Epistemology, Blackwell
Publishers, 1999
Quine,
W.V.O.: Epistemology Naturalized in ‘Ontological
Relativity and other Essays’; Columbia University Press, 1969;reprinted in: Kornblith, H. (Ed.): Naturalizing Epistemology; The
Massachusetts Institute of Technology, 1985
Rorty,
R.: Philosophy and the Mirror of Nature; Princeton University
Press, 1980
Sosa,
E.: Nature Unmirrored, Epistemology Naturalised; in Sosa, E.
(Ed.): Knowledgein Perspective, Selected Essays in
Epistemology; Cambridge University Press, 1991
Stroud,
B.: The Significance of Naturalized Epistemology; in
Kornblith, H. (Ed.): Naturalizing Epistemology; The Massachusetts
Institute of Technology, 1985
Stroud, B.: The Significance of
Philosophical Scepticism; Clarendon Press, 1984
1Quine,
W.V.O.: Epistemology Naturalized in ‘Ontological
Relativity and other Essays’; Columbia University Press, 1969;reprinted in: Kornblith, H. (Ed.): Naturalizing Epistemology;
The Massachusetts Institute of Technology, 1985, p.19
2
Everitt, N.; Fisher, A.: Modern Epistemology, A New Introduction;
McGraw-Hill Inc., 1995, p.181; and, Sosa, E.: Nature Unmirrored,
Epistemology Naturalised; in Sosa, E. (Ed.): Knowledgein
Perspective, Selected Essays in Epistemology; Cambridge University
Press, 1991, p.101
3
Quine, op cit, p.24
4
Kornblith, H.: In Defence of a Naturalised Epistemology; in
Greco, J; Sosa, E. (Eds.): The Blackwell Guide to Epistemology,
Blackwell Publishers, 1999, p.165
5
Quine, op cit, p.27
6
Quine, op cit, p.19
7
Quine, ibid
8
Sosa, op cit, p.102
9
Stroud, B.: The Significance of Naturalized Epistemology; in
Kornblith, H. (Ed.): Naturalizing Epistemology; The Massachusetts
Institute of Technology, 1985, pp.71
10
Koppelberg, D.: Why and how to naturalise epistemology; in
Barret, R. B.; Gibson, R. F. (Eds.): Perspectives on Quine; Basil
Blackwell, 1990, p.205
11
Kornblith, H.: In Defence of a Naturalised Epistemology; in
Greco, J; Sosa, E. (Eds.): The Blackwell Guide to Epistemology,
Blackwell Publishers, 1999, p.166
12
Rorty, R.: Philosophy and the Mirror of Nature; Princeton
University Press, 1980, p.255
13
Stroud, B.: The Significance of Philosophical Scepticism;
Clarendon Press, 1984, p. 241-54
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