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Naturalizingepistemology/editedbyHilaryKornblith.- 2nded.
p. em.
"ABradfordbook."
Includesbibliographicalreferencesandindex.
ISBN0-262-11180-2.- ISBN0-262-61090-6(pbk.)
1. Knowledge, Theoryof. I. Kornblith, Hilary.
BD161.N29 1993
121-dc20 93-23976
CIP
Introduction: What Is
Naturalistic Epistemology?
Hilary Kornblith
In recent years the naturalistic approach to epistemology has been
gaining currency. The goal of this introduction is to answer my title
questionandatthesametime toplacetheessaysthatfollowinappro
priate perspective.
Three Questions
Consider the following three questions.
1. How oughtwe to arrive atourbeliefs?
2. How do we arrive atour beliefs?
3. Are the processes by which we do arrive atourbeliefs the ones by
which we ought to arriveatour beliefs?
Different theorists will answer these questions differently. The topic
I wish to deal with here has to do with the relations among these
three questions. If we wish to answer all of these questions, which
should we deal with first? Can any of these questions be answered
independentlyofthe others, orwill theanswers to eachconstrainthe
range ofanswers we mightgive to those remaining? Justas different
theorists disagree about answers to questions 1, 2, and 3, there are
disagreements about the relations among these questions. What I
want to suggest here is that what is distinctive about the naturalistic
approach to epistemologyis its view about the relations among these
three questions.
The Traditional View
Oneview, whichIwilllabel the traditionalview, suggestsa strategyof
divide and conquer. Question 1 is to be assigned to philosophers,
.."....
"~..,r'W'I-:>
Pstd'l~L.cSjSi·S
Hilary Kornblith 2
'Q~
question 2 to psychologists. Each of these groups is to conduct its
research independently of the other. When both groups have com
pleted their work, they must get together to answer question 3. It is
permissible, of course, for philosophers and psychologists to meet
prior to each group's completion ofits assigned task. Such meetings
will allow them to check progress onquestion3. These meetings will
not, however, have anyeffectonworkon questions 1or 2. Question
1 is in the bailiwick of philosophers; question 2 in the bailiwick of
psychologists; and the answer to question 3 is produced by compar
ing the answers to questions 1and 2.
Most research in philosophy as well as psychology seems to be
guided by the traditional view. On the philosophical side consider
onekind ofanswer thathas beenoffered toquestion1: the coherence
theory ofjustification@oherence theorists hold, roughly, that in de
ciding whether to accept or reject any statement, one ought to con
sider how well it fits in with or coheres with one's otherbeliefs; one
ought to adopt beliefs cohering with beliefs one already haiJWhat
ever the merits of this view, it seems to have nothing to do with any
possible answer to question 26uppose that psychologists were to
discover that people actually arrive at their beliefs by some kind of
nonconscious mechanism that measures the coherence of candidate
beliefs with the body of beliefs already held; candidates that cohere
are adopted and those that do not are rejected. What bearing would
this psychological theory have on the merits of the coherence theory
of justification as an answer to question I? None, it seems. How we
actually arrive at our beliefs need have nothing to do with how we
ought to arrive at them. By the same token if we are evaluating the
merits of some psychological account of belief acquisition, a pur
ported account ofhow people actually arrive at their beliefs in some
situation, theories about how we ought to arrive at our beliefs seem
tobeirrelevant.
An analogy with ethics seems apt here. Consider the following
three questions abouthumanaction:
A. How ought people to act?
B. How do peopleact?
C. Do people act the way they ought?
These questions bear the samerelations to each otheras questions I,
2, and 3. Moreoverit seems clear that it is the job ofethical theorists
What Is Naturalistic Epistemology? 3
to answerquestionAandpsychologistsconcernedwithhumanmoti
vation to answer question B. Only by comparing the results ofthese
two independent investigations will the answer to C emerge. Note
how absurd it would be for a philosopherto objectto a psychological
account of how people act on the grounds that action of that sort is
immoral. It would be equally absurd ifa psychologist were to object
toa philosophicalaccountofhowweoughttoactonthe groundsthat
people do not act that way. There is a straightforward explanation
of the absurdity of these challenges. The normative questions that
philosophersaskarecompletelyindependentofthe descriptive ques
tions psychologists ask. This seems to be true not only in the case of
questions A and Bbutalso in the case ofquestions 1and 2.
Idonotmean toendorsetheargumentsofthissectionforthe tradi
tional view, nor do I mean to suggest that no other arguments for it
are available. Instead I hope only to have presented enough of the
traditional view and its motivation so that it may clearly be distin
guished from a naturalistic approach to questions 1, 2, and 3.
The Replacement Thesis
I take the naturalistic approach to epistemology to consist in this:
question 1 cannot be answered independently of question 2. Ques
tions about how we actually arrive at our beliefs are thus relevant to
questions about how we ought to arrive at our beliefs. Descriptive
questions about belief acquisition have an importantbearing on nor
mative questions aboutbeliefacquisition.
There are, of course, different camps within the naturalistic ap
proach; naturalistic epistemologists differ on how direct a bearing
psychology has on epistemology. The most radical view here is due
to Quine:
Epistemology still goes on, though in a new setting and a clarified status.
Epistemology, or something like it, simply falls into place as a chapter of
psychology and hence of natural science. Itstudies a natural phenomenon,
viz., a physicalhumansubject. This human subjectis accorded a certainex
perimentallycontrolledinput--certainpatterns ofirradiationinassortedfre
quencies, for instance-and in the fullness of time the subject delivers as
outputa descriptionofthe three dimensionalexternalworld and its history.
Therelation betweenthe meagerinputand the torrentialoutputisarelation
that we are prompted to study for somewhat the same reasons thatalways
promptedepistemology;namely, inordertoseehowevidencerelates tothe
ory, and in what ways one's theory of nature transcends any available evi-
dence.I (:+." --"
Hilary Kornblith 4
I will speak of the view that epistemological guestions may be re
placed by psychological questions as the replacement thesis.
Quine'sargumentforthereplacementthesisinchapter1isthis: the
, history of epistemology is largely the history of the foundationalist
Co program. Foundationalists tried to show that there is a class of be-
liefs-typicallybeliefs aooutourownsenseexperience-aboutwhich
.,. it is impossible to be wrong. These beliefs were held to be sufficient
",' to justify the rest ofour beliefs; thus, in addition to identifying those
beliefs thatwould serveas the foundation ofknowledge, foundation-
alists sought to show how foundational beliefs provide us with good
reason for adopting the remainder ofourbeliefs. The history ofepis
temology shows that the foundationalist program has faced one fail
ure after another. The lesson to be learned from these failures,
according to Quine, is not just that foundationalists had mistakenly
answered question 1in claiming that theappropriate way to arriveat
one'sbeliefsis tobeginwithbeliefsaboutwhichonecannotbewrong
and build upon that foundation. Rather, according to Quine! founda
tionali~t>were asking the wrong guestions. Once we see the sterility
of the foundationalist program, we see that the only genuine ques
tions thereare to askabout the relation betweentheoryandevidence
andabout theacquisitionofbeliefare psychologicalquestions. In this
view question 2is relevant to question 1because it holds all the con
tent that is left in question 1. The relation between these two ques
tions is much like the relation atheists believe to hold between
questions about God's actofcreation and questions about the details
of, for example, thebigbang; the latterquestions exhaustall the con
tent there is in the former questions.
One illustration of the way in which traditional epistemological
questions have become transformed through our newly gained un
derstanding forms the heart of chapter 3. Philosophers have long
asked, how is knowledge possible? This question has been under
stood for centuries as a requestfor a responJie to t skeptic, and the
result has been the various attempts to work out the details of the
foundationalist program. What we are now in a position to under
standis preciselyhowfoundationalists misinterpretedthis important
question. If the question about the possibility of knowledge is inter
pretedasa request torespond to the skepticonhisorherownterms,
thenanyattempt to answer the question is doomed to failure. Quine
argues, however, that this interpretation mislocates the very worries
that gave rise to the question in the first place. It is through the rise
What Is Naturalistic Epistemology? 5
of science that we were first led to question the limits and possibility
ofknowledge. As science made clear the falsity ofour former beliefs
and our susceptibility to illusion, the question naturally arose as to
whether the beliefs we arrive at, even under the best of conditions,
are likely tobe true. In shortthe question aroseas to whetherknowl
edge is possible. Insofar as this question arises from within science,
we maycallonthe resources ofscience toanswerit. Farfrom making
epistemology a necessary prerequisite to doing science, this makes
,epistemology continuouswith t 'ficenter e.
Fortunately, when we turn to science to answer our question, we
are notdisappointed. As Quine suggests, "Thereis some encourage
mentin Darwin." Creatures whose beliefgeneratingmechanisms do
notafford themcognitive contactwiththe world "havea patheticbut
praiseworthy tendency to die before reproducing their kind." Since
believing truths has survival value, the survival of the fittest guaran
tees thatourinnateintellectualendowmentgives us a predisposition
forbelievingtruths. Knowledge is thus notonly possiblebuta neces
sary by-productofnatural selection.
This Darwinian argument may be thought to provide a motivation
for the replacement thesis quite different from that offered by Quine
in chapter 1. Ifthe Darwinian argument can be worked outin detail,
itmayprovidea wayoftacklingthe originalthreequestionsbytaking
on question 3 first. If nature has so constructed us that our belief
generating processes are inevitably biased in favor of true beliefs,
then it must be that the processes by which we arrive at beliefs just
are those by which we ought to arrive at them. Question 3 is thus
answered with an emphatic affirmative, and we may move on to the
remaining two questions. Ifwe know in advance, however, that we
arriveatbeliefsin justthe way we ought, oneway to approachques
tion 1 is just ~ s chology. In discovering the processes by
which we actuall arrive at beliefs, we are thereby discovering the
processesbywhich we oughtto arriveatbeliefs. The epistemological
enterprise maybe replaced byempiricalpsychology.
Notice thatthe attempt to defend the replacement thesisbywayof
the Darwinian argument requires that the conclusion of that argu
mentbe givena very strongreading. Someonewhoconcludesonthe
basis of natural selection that the processes by which we acquire be
liefs must be roughly like the processes by which we ought will not
be in a position to defend the replacement thesis. If psychological
investigationis to be able to replace epistemologicaltheorizing, there
Hilary Kornblith
must be a perfect match between the processes by which we do and
those by which we ought to acquire beliefs. Without such a perfect
match, the results of psychological theorizing will only give an ap
proximate answer to question I, and epistemology will be called on
to make up the slack. Psychologywould thus be strongly relevant to
epistemology, and this version of the Darwinian argument would
thus motivatea versionofnaturalisticepistemology, butthe resulting
viewwouldbe far weaker than the replacementthesis.2
Still a third argument for the replacement thesis is to be found in
such writers as Davidson,3 Dennett,4 Harman,5 and, once again,
Quine.6In Harman's version, the argumentis as follows:
We normally assume that there are basic principles ofrationality that apply
to all normal human beings.... We come to understand someone else by
coming to appreciate thatperson's reasons for his orherbeliefsandactions,
orby seeing how that person made a mistake. Someone who reasoned in a
fundamentally different way from the wayinwhichwe reason would really
and truly be unintelligible to us.... In assuming, as we normally do, that
wecanmakesenseofotherpeople, givensufficientinformationaboutthem,
wepresupposethateveryoneelseoperatesinaccordancewiththesamebasic
principlesas wedo.7
As Harman makes clear, he does not mean to bearguing onlyfor the
conclusionthatwe all arrive atourbeliefsin the same waybutrather
thatrationalbeliefacquisitionconsistsofarrivingatbeliefsintheway
we all do. In Harman's view since individuals who reason in a way
different than we do would be unintelligible to us, we would not
count them as rational; the only rational individuals are thus ones
whoreasonaswe do. Onceagainthisallowsus toapproachtheorigi
nalthreequestionsbyansweringquestion3first, and inansweringit
in the affirmative, the wayis pavedfor the replacementofepistemol
ogy by psychology. It should also be noted that the conclusion of
Harman's argument must be interpreted in quite a strong way ifit is
to serve as an argument for the replacement thesis. When Harman
argues that someone who reasons in a fundamentally different way
wouldbeunintelligibletous, hecannotsimplymeanthatlargediffer
ences in the way individuals reason would result in mutual uninter
pretability, for this viewis compatiblewith the claimthatindividuals
differ from one another in minor respects in the way they reason.
Psychologycouldthendescribe the differentwaysinwhichindividu
als reason but it would be impotent to pick out which of these ways
(ifany) were rational. Harman mustthereforebe arguing for the con-
What Is Naturalistic Epistemology? 7
clusionthatanydifferencewhatsoeverinthewaysindividualsreason
would result in mutual uninterpretability. Weaker conclusions than
this will not supportthe replacement thesis.
We are now in a position to distinguish between a strong and a
weak version of the replacement thesis. The strong version of the
replacement thesis is argued for by Quine in chapter1. Quine argue
not only that epistemological questions may be replaced by psycho
logical questions but also that this replacement must take place; psy
chological questions hold all the content there is in epistemological
questions. On this view psychology replaces epistemology in much
the same way that chemistry has replaced alchemy. The other two
arguments examined for the replacement thesis, however-the Dar
winian argument and the argument from mutual interpretability
suggest a weak version of the replacement thesis. In this view psy
chologyand epistemologyprovide two differentavenues for arriving
at the same place. Psychologymay replace epistemologybecause the
processes psychologistsidentify as the ones bywhich we do arriveat
ourbeliefswillinevitablyturnouttobethe very processesepistemol
ogists would identify as the ones by which we ought to arrive at our
beliefs. Thus even if all epistemologists were to give up their trade
and turntoauto mechanics, thequestions theytried toanswerwould
neverthelessbeaddressed, inadifferentguise, bypsychologists. This
view is carefully scrutinized in chapter 15 by Stephen Stich, "Could
Man Be an IrrationalAnimal?"
The Autonomy of Epistemology
There is a world of difference between the strong and the weak ver
sion ofthe replacement thesislfhe questionat issueis theautonomy
of epistemologi]Are there legitimate epistemological questions that
are distinct in content from the questions of descriptive psychology?
Advocatesofthe strongversionofthereplacement thesisanswerthis
question in the negative, advocates ofthe weak version answer it in
the affirmative. The consequences of the strong version of the re
placement thesis for the study of epistemology are clear: epistemol
ogy must go the way of alchemy and be absorbed into another
science. In this section I examine some of the consequences of the
weak replacement thesis for epistemological theorizing. Ifepistemol
ogy is an autonomous discipline but subject nevertheless to the con
straints ofthe weak replacement thesis, what will epistemology look
Hilary Kornblith 8
like? What kind ofrelationship does this dictate between psychology
andepistemology?
If the weak replacement thesis is true, epistemologists need not
fear that theywill bereplaced bydescriptive psychologists. The weak
replacement thesis is a two-way street. If psychologists and episte
mologists inevitably will receive the same answers to the different
questions they ask, psychologists are just as subject to replacement
by epistemologists as epistemologists are by psychologists. We may
leave the unemployment issue aside, however, for if the weak re
placement thesis is true, no kind of replacement is likely to go on.
Eitherdisciplinecouldreplacetheother, butthereareextremelygood
pragmatic reasons why they shouldnot.
Ifthe thesisunderdiscussionis true, the psychologyofbeliefacqui
sition and epistemology are two different fields, which ask different
butequallylegitimatequestionsand havedifferentmethodologies. In
spite of these differences a complete (and true) psychology of belief
acquisition will describe the same processes that a complete (and
true) epistemology will prescribe. That these two fields will, when
complete, singleoutthesameprocessesofbeliefacquisitiondoesnot,
however, suggest that at stages short of completion, the processes
singled out by philosophers and those singled out by psychologists
will match perfectly. Indeed it is clear that if pursued independently
ofone another, anything shortofa complete psychology would look
very different from anything short of a complete epistemology, in
spite of their ultimate convergence. Because the two fields deal with
differentquestions and because these questions are approached with
different methodologies, processes that are easily identified by psy
chologists as ones that occur in us may not easily be identified by
philosophers as ones that ought to be used; by the same token pro
cesseseasilyidentifiedbyphilosophersas onesweoughtto use need
not be easily identified by psychologists as processes we actually
make use of. The upshot is that even if the weak replacement thesis
is true, noactualreplacementcanoccuruntileachfieldhascompleted
its work. Moreover, in order to hasten progress, philosophers and
psychologists ought to be eagerly examining each other's work. If
philosophers correctly identify some process as one by which we
ought to arrive at our beliefs, psychologists will thereby know, even
iftheyhave riotindependentlydiscoveredit, thatitoccursinus. Sim
ilarly if psychologists identify some process as one that occurs in us,
epistemologists can be confident that this is a process by which we
What Is Naturalistic Epistemology? 9
ought to arrive at our beliefs, even if they have not yet reached that
conclusion independently. Thus if the weak replacement thesis is
true, we can look forward to rapid progress in both psychology and
epistemology as a result of their interaction, rather than either field
beingco-opted by the other.
Psychologism
Psychologism is the view that the processes by which we ought to
arrive at our beliefs are the processes by which we do arrive at our
beliefs; in short it is the view that the answer to question 3 is "yes."
Ifthe weak replacement thesis is true, then so is psychologism. Nev
ertheless it may be that psychologism is true and yet the weak re
placement thesis is false. In this section I explain how that might
be so.
ConsiderAlvinGoldman'sanswerto question1inchapter5. Gold
man suggests that we ought to arrive at our beliefs by processes that
are reliable, that is, by whatever processes tend to produce true be
liefs. Let us assume that Goldman is correct, and let us also assume,
as Goldman does not, that psychologism is true. It thus follows that
the processes by which we actually arrive at our beliefs are reliable.
Even though, as we are assuming, a complete psychology of belief
acquisitionwoulddescribethesameprocessesGoldman'stheorypre
scribes, acompletedpsychologywouldlooknothinglikeacompleted
Goldman-style epistemology. It would not do for a psychologist to
say merely that the processes by which we arrive at our beliefs are
reliable and leave it at that. Obviously a complete psychological the
ory must be far more detailed and specific. The added specificity of
the psychologicalaccountisnotmerelyunnecessary, however, to an
sweringtheepistemologicalquestion, ifanythinglikeGoldman'sthe
oryis correct; the psychological theory is simply spelled outin terms
at the wrong level ofgenerality to do epistemological work. Imagine
that we have a completelistofall thebeliefacquisitionprocessesthat
take place in human beings. This list, it seems, will not answer our
epistemological question (even assuming psychologism to be true),
for we wish to know what all these processes have in common in
virtue ofwhich we oughtto acquirebeliefsbyway ofthem. Our psy
chological theory will not answer this question. By the same token
our philosophical theory, even ifgiven in full detail, will not answer
all ourpsychologicalquestions.
Description:The second edition of Naturalizing Epistemology has been updated and expanded to include seven new articles that take up ongoing debates in the field. As with the first edition, it explores the interaction between psychology and epistemology and addresses empirical questions about how we should arri
