epistemic justification:
(EVI) Person S is justified in believing proposition p at time t
if and only if S's evidence for p at t supports believing p.
As evidentialism is a thesis about epistemic justification, it is a
thesis about what it takes for one to believe justifiably, or
reasonably, in the sense thought to be necessary for knowledge.
Particular versions of evidentialism can diverge in virtue of their
providing different claims about what sorts of things count as
evidence, what it is for one to have evidence, and what it is for
one's evidence to support believing a proposition. Thus, while (EVI)
is often referred to as the theory of epistemic justification known as
evidentialism, it is more accurately conceived as a kind of epistemic
theory. In this light, (EVI) can be seen as the central, guiding
thesis of evidentialism. All evidentialist theories conform to (EVI),
but various divergent theories of evidentialism can be formulated.
Before turning to these issues, it is worth noting that evidentialism
is also a prominent theory in the philosophy of religion.
Evidentialism in the philosophy of religion has its own set of
controversies, but this entry will not cover them. On evidentialism in
the philosophy of religion, see Alvin Plantinga's classic article,
"Reason and Belief in God." For a more extended discussion, see
Plantinga's Warranted Christian Belief.
1. A Brief Prima Facie Case
When we think about what it takes for one to believe reasonably or
justifiably, we think that one has to have good reasons (or, more
accurately, adequate reason for thinking the proposition in question
is true). We think that one is not believing as one should when one
believes something for no reason whatsoever or for very weak reasons.
This dependence on reasons seems to be central to the very concept of
justified belief. It should be no surprise, then, that the traditional
view holds that one is justified only if one has adequate reasons for
belief. Thus, evidentialism can be thought of as the default, or
commonsense, conception of epistemic justification. Indeed, we can see
the centrality of this conception of justification throughout the
history of philosophy, especially in its grappling with the problem of
skepticism. In order to justify denying skeptical claims, we want to
know what reason we have for believing that skepticism is false.
Traditional accounts have looked to one's available evidence or
reasons for an answer.
Naturally, then, we see this traditional conception reflected in the
writings of many influential philosophers. David Hume, for example,
writes that the "wise man. . . proportions his belief to the
evidence," and he proceeds with this as his epistemic ideal (73).
Bertrand Russell endorses the view that "[p]erfect rationality
consists . . . in attaching to every proposition a degree of belief
corresponding to its degree of credibility," credibility functionally
depending on evidence (397-398). W.K. Clifford writes that "it is
wrong always, everywhere, and for anyone to believe anything upon
insufficient evidence" (518). Such quotations help to illustrate the
dominance of the view that justified belief depends upon one's having
good reasons or evidence. Though this by no means settles the issue,
it does provide reason to try to work out a theory of justification
that appeals solely to evidence. The remainder of this entry turns
toward a detailed consideration of the theory itself.
2. Developing the Theory
Richard Feldman and Earl Conee, two leading defenders of
evidentialism, have explicitly defined evidentialism as a thesis about
the justificatory status of all of the doxastic attitudes: belief,
disbelief, and suspension of judgment. They write that doxastic
attitude, d, toward p is justified for one at t if and only if one's
evidence at t supports one's taking d towards p (15). So understood,
evidentialism is not just a thesis about justified belief, it is also
a thesis about justified disbelief and the justified withholding of
belief. Only one doxastic attitude towards a proposition is justified
for a person at a time, and this is a function of one's evidence.
Here, I focus on the core of evidentialism—the thesis about justified
belief given in (EVI)—both for simplicity and because most treatments
and criticisms of evidentialism focus on it. What is said about (EVI)
can be extended naturally to the rest of the doxastic attitudes and
thereby applied to Feldman and Conee's explicit thesis.
a. The Justification of Propositions v. The Justification of Beliefs
Before proceeding, it is crucial to nail down more exactly what
evidentialism is a theory of. As I have defined it in (EVI),
evidentialism is the thesis that one is justified in believing a
proposition at a time if and only if one's evidence at that time
supports believing that proposition. (EVI) does not entail that
whenever one has adequate evidence for p one believes p justifiably.
This is for two reasons. First, one can be justified in believing p
even if one fails to believe it. For example, one might not believe p
simply because one fails to consider whether or not p is true, yet one
may nevertheless have good enough reason to think p is true and so be
justified in believing p.
Second, one can have good enough reason to believe p and still believe
it as a result of something other than this good reason. One might
believe it as a result of wishful thinking, for example. In such a
case, the evidentialist holds that the person is justified in
believing the proposition in question but, nevertheless, believes it
unjustifiably. One believes it for or because of the wrong reasons.
One way of putting the difference here is by saying that evidentialism
is a thesis regarding propositional justification, not a thesis about
doxastic justification. That is, evidentialism is a thesis about when
one is justified in believing a proposition, not a thesis about when
one's believing is justified. The latter requires not just that one
have good reason to believe but also that one believe for those good
reasons.
b. Evidence
As introduced above, evidentialism is a kind of theory of epistemic
justification; one can formulate various divergent evidentialist
theories by providing different analyses of its constituent concepts.
The present section focuses on the central notion of evidence and
explicates the various ways that one can restrict the sorts of things
that count as evidence. Sections 2c. and 2d. turn to complexities in
other parts of (EVI). Together, these three sections illustrate the
diversity of possible evidentialist theories.
Evidence for or against p is, roughly, any information relevant to the
truth or falsity of p. This is why we think that fingerprints and DNA
left at the scene of the crime, eye-witness testimony, and someone's
whereabouts at the time the crime was committed all count as evidence
for or against the hypothesis that the suspect committed the crime.
The sort of evidence that interests the evidentialist, however, is not
just anything whatsoever that is relevant to the truth of the
proposition in question. The evidentialist denies that such facts
about mind-independent reality are evidence in the sense relevant to
determining justification. According to (EVI) only facts that one has
are relevant to determining what one is justified in believing, and in
order for one to have something in the relevant sense, one has to be
aware of, to know about, or to, in some sense, "mentally possess" it.
The sort of evidence the evidentialist is interested in, therefore, is
restricted to mental entities (or, roughly, to mental "information").
In addition, it is only one's own mental information that is relevant
to determining whether one is justified in believing that p. For
example, my belief that Jones was in Buffalo at the time the crime was
committed is not relevant to determining whether you are justified in
believing that Jones committed the crime.
Evidentialist theories can agree on this much while still providing
differing accounts of evidence. For example, one might think that only
one's own beliefs can provide one with reason to believe something, as
many coherentists do. An evidentialist might then hold that only
belief states are evidential states. One's experiences (that is,
experiential states) then would not be evidentially or justificatorily
relevant. The standard view of evidentialism, however, is that at
least beliefs and perceptual states are evidential states. Not only
what you believe but also what you experience can provide you with
reason to believe that something is the case. Yet one does not have to
stop there. One, for example, might also count memories, apparent
memories, or seemings-to-be-true as kinds of evidence. In the end,
what sorts of states one takes to be evidential will depend both on
one's intuitions about what sorts of things can provide one with
genuine reason to believe and also on one's strategy for responding to
objections.
It is worth noting that while evidentialists have available many
options about what to count as kinds of evidence, not just anything
mental can properly be classified as evidence. In general, only those
states or properties that are themselves informational (or at least
can directly and on their own "communicate" information to the
subject) can properly be classified as evidential states or
properties. Regardless of whether one's feeling of pain is an
informational state, it does, so to speak, directly or on its own
"communicate" information to one; so it is open to the evidentialist
to classify it as an evidential state. By contrast, one's ability to,
e.g., identify complex geometrical shapes in one's visual field is not
itself a kind of evidence. (Even though this ability will undoubtedly
provide one with evidence one would otherwise not possess.) The
ability to identify complex geometrical shapes in one's visual field
is not a kind of evidence because it is neither an informational
state, nor is it a state that directly and on its own "communicates"
information to one. Instead, it is always something else that gets
"communicated" to one via that ability. In general, therefore,
cognitive abilities are not properly considered as part of one's
evidence. As we will see below, though, this is not to say that one's
cognitive abilities are completely irrelevant to justification on
every evidentialist view.
c. Having Evidence
As alluded to above, not just any evidence whatsoever is relevant to
determining whether one's belief is justified; it is only the evidence
that one has that is so relevant. The obvious restriction this imposes
is that one's evidence includes only one's own mental states. One
option, then, is to hold that one's evidence at a time (or,
alternatively, the evidence one has at a time) consists in all of the
evidential mental states that obtain in the person at that time,
including both occurrent and nonoccurrent mental states. On this view,
one's evidence includes not only one's present experiences and those
beliefs presently "before one's mind" but also stored or standing
beliefs, even if one is not presently able to recall or consciously
consider them.
To see how this account of having evidence affects the consequences of
the theory, consider the following example. Suppose that I believe
that most television newscasters reliably report the day's news. I
find that television newscasters almost always report the day's
stories in ways consistent with that reported by other news outlets.
For example, if the newscaster were to report that a fire occurred on
Elm Street, I would also be able to find a report in the newspaper
confirming that a fire did, indeed, occur on Elm Street. When I
discuss this topic with people, they tend to agree that this is the
case, and I have no strong evidence against this belief. It seems,
then, that I justifiably believe that most television newscasters
reliably report the news. Also suppose that fifteen years ago I heard
reliable testimony that one newscaster, Mick Stuppagin, almost always
provides incorrect reports. At the time, I believed that Mick was a
very unreliable newscaster. Suppose, however, that although my belief
that Mick's reports are unreliable and the testimony that such is the
case are still stored in my long-term memory, I am presently unable to
recall them. If someone mentions Mick Stuppagin and asks whether I
think he is a reliable newscaster, I may form the belief that he is a
reliable newscaster on the basis of my justified belief that most
newscasters are reliable.
On the view developed above, I would be believing unjustifiably, since
I have outweighing evidence against p. I would not be justified in
believing that Mick is a reliable newscaster even though I may be
utterly unable to recall my evidence against this belief, even though
my so believing may be completely blameless, and even though it may
seem to me on deep reflection that I am believing as I should. Some
may find this counterintuitive and, as a result, may want to formulate
a more restricted account of having evidence.
One such option is to hold that the evidence one has at a time is
restricted to one's occurrent evidential states—i.e., those states
involving one's current assent, those presently "before one's mind,"
so to speak. On this account of having evidence, my stored memory
belief that Mick Stuppagin is an unreliable newscaster is not evidence
that I have at the present time. Furthermore, it is also not clearly
true that I have as evidence my belief that most television
newscasters reliably report the day's news, and it is doubtful that my
testimonial and inductive evidence for this belief is properly
considered evidence that I presently have. The justificatory status of
my present belief about Mick Stuppagin will depend solely on my
occurrent evidential states. (The details of the case would need to be
filled in order to determine whether or not the theory implies that
belief is justified.)
The difficulty for this view is to show how such a restricted view of
one's having evidence can account for the justification of all of the
beliefs we think are justified. For instance, we think we have some
non-occurrent beliefs that are justified. We need an explanation of
this. Similarly, it seems that as soon as I occurrently entertain the
proposition that George Washington was the first president of the
United States, I am justified in believing it, and its being so
justified does not depend upon my consciously recalling anything.
Those who restrict the evidence one has to one's occurrent states need
either to provide an explanation of this or to in some way explain
away these common intuitions.
Other accounts of having evidence lie between these two extremes. A
more typical "internalist" account might hold, for example, that the
evidence one has at a time is that which is easily available to one
upon reflection, so not all of one's beliefs count as evidence that
one has at a time. On this account, I am presently justified in
believing that Mick is a reliable newscaster if and only if my stored
memory belief that Mick is an unreliable newscaster (and its
supporting evidence) is not easily available to me upon reflection.
Various other accounts of having evidence can be developed that allow
for varying degrees of availability or varying amounts of reflection.
Guiding each account of having evidence are intuitions regarding cases
similar to that above and intuitions regarding the extent to which
justification is deontological.
We can conclude from the above that evidentialist theories can be
formulated so as to account for widely divergent intuitions regarding
cases. Furthermore, without a specific account of what it is for one
to have evidence, it is not clear which proposed cases are to count as
counterexamples to the theory.
d. Support
Recall that on the evidentialist view, S is justified in believing p
at t if and only if S's evidence for p at t supports believing p. We
have already seen how evidentialists can provide different accounts of
evidence and having evidence. The present section focuses on
complexities with the notion of support.
Perhaps the most obvious issue that needs to be addressed in order to
understand what it is for one's evidence to support believing a
proposition is the degree to which one's evidence must support that
proposition in order for one to be justified in believing it. Again,
this will vary from account to account. One standard account
understands it as follows: one is justified in believing a proposition
only if the evidence that one has makes it more likely to be true than
not. The likelihood of truth given one's evidence has to be greater
than 0.5 in order for one to be justified in believing the
proposition, but the threshold required for knowledge might be much
higher. In order to know that p, one might not merely have to
justifiably believe that p; one might have to justifiably believe it
to a certain degree.
This way of understanding the degree of support required in order for
one to be justified in believing p is absolute, or we might say
non-contextual. The degree required is the same across all possible
cases. By contrast, Stewart Cohen presents a contextualist version of
evidentialism. On his account, the degree to which one's evidence must
support a proposition in order for one to be justified in believing it
will fluctuate with the conversationally determined standards that
govern attributions of justification and knowledge. An immediate
result is that one's evidence for p may be enough to make believing p
justified in one context (where the conversationally-determined
standards for justification are relatively low) while failing to make
believing p justified in another context (where the standards for
justification are much higher). Evidentialism is, therefore,
consistent with both contextualist theories of justification and
non-contextualist theories of justification.
A further, more central epistemological issue regarding support has to
do with the structure of justification. Evidentialism may be combined
with foundationalism, coherentism, a "mixed" view such as Susan
Haack's foundherentism, or any other theory of the structure of
justification. Each theory may be incorporated into evidentialism by
understanding them as providing an account of the proper nature of
epistemic support. Since foundationalism is far more dominant than the
other theories, in what follows I will present one way of developing
evidentialism with regard to it.
According to foundationalism, a belief is justified if and only if:
either it is a foundational belief or it is supported by beliefs which
either are themselves foundational beliefs or are ultimately supported
by foundational beliefs. From the previous section, we have seen that
it is only the evidence one has that is relevant to determining
whether a belief is justified. Of all of this, foundationalism implies
that only that evidence which is non-doxastic, foundational, or
ultimately supported by a foundational belief is capable of supporting
(or conferring positive justificatory status on) a belief.
(Non-doxastic evidential states may include appearance states, direct
apprehensions, rational intuitions, and seemings-to-be-true. For the
foundationalist, some such evidential states are crucial as only they
can justify the foundational beliefs.)
Assuming this framework, we can proceed as follows. In order to
determine whether one is justified in believing that p, first isolate
the portion of the evidence that is non-doxastic, foundational, or
ultimately supported by a foundational belief. Only this is capable of
justifying a proposition. Next, if the proposition under consideration
is believed, subtract that belief and anything else whose support
essentially depends on (or traces back to) that belief. (This last
modification is intended to accommodate the foundationalist thesis
that only the more basic can justify the less basic. See, for example,
the discussion in section 3e. below.) Finally, determine whether this
portion of one's evidence makes the proposition more likely true than
not. If so, then it is prima facie supported by one's evidence (and
thus prima facie justified). If not, it is unjustified, for it is not
supported by the evidence one has that is able to justify one's
believing the proposition.
Note that I have had to add a prima facie qualification here. This is
due to the, at least, apparent possibility of one's support for a
belief being defeated by other evidence one has that is neither
non-doxastic, nor foundational, nor ultimately supported by
foundational beliefs. An unjustified belief may be able to defeat the
positive justification one has for believing p, but such unjustified
beliefs have so far been excluded from consideration. In such a case,
we may want to say that one would not be justified in believing p.
3. Objections
The aim in this section is to provide a sampling of objections that
have been raised against evidentialist theories of justification. The
aim is not to respond to these objections on behalf of the
evidentialist nor to evaluate their strength. While the following are
not objections to all possible versions of evidentialism, together
they illustrate the difficulty in formulating a complete and adequate
evidentialist theory. The chief difficulty for the evidentialist is to
develop the theory in a way that avoids all such objections and does
so in an independently motivated and principled way.
a. Forgotten Evidence
One kind of objection stems from the widespread occurrence of one's
forgetting the evidence that one once had for some proposition. We can
distinguish between two sorts of cases here. According to the first
sort, though one once had good evidence for believing, one has since
forgotten it. Nevertheless, one may continue to believe justifiably,
even without coming to possess any additional evidence. Evidentialism
appears unable to account for this. According to the second sort of
case, when one originally came to believe p, one had no evidence to
support believing p. Perhaps one originally came to believe p for very
bad reasons. Consequently, just after one formed the belief, one was
not believing justifiably as one's total evidence did not support
believing that p. Suppose, though, that one has since forgotten why it
is that one originally formed the belief and also has forgotten all of
the evidence one had against it. Since it doesn't seem as though in
the interim one has to have gained some additional evidence for p, one
might think that the subject of the second case remains unjustified in
believing p. The relevant beliefs in both cases appear to be on an
evidential par: neither belief seems to be supported by adequate
evidence. The objection is that there, nevertheless, is a
justificatory difference between the two cases, and evidentialism is
unable to account for this.
The details of the cases proposed along these lines are crucial, for
evidentialists may be able to motivate a denial of the critic's
justificatory assessment of one of the cases. This, however, is only
of help when combined with an explanation for the justification of
memory beliefs in general and memory beliefs involving forgotten
evidence in particular.
Here evidentialists can appeal to the notion of evidence and to what
sorts of states or properties are properly classified as evidential.
For example, one may argue that the "felt impulse" to believe the
proposition recalled from memory or its "seeming to be true" is itself
a kind of evidence. On this account, in the first case one is
justified in believing p because one does have evidence that supports
believing p. The supporting evidence is the proposition's "seeming to
be true" or the "felt impulse" that accompanies the belief, but this
very same evidence is present in the second case as well. Furthermore,
this "felt impulse" or "seeming to be true" will necessarily accompany
any memory belief, so there will be no cases along the lines of the
second sort in which one has no evidence to support believing p. As a
result, the critic's appraisal of the second case is mistaken. In the
absence of overriding counter-evidence, one's memory belief is
justified, so the correct appraisal of the second case holds that one
is justified in believing p. In short, the critic's justificatory
assessment of the second case is mistaken.
b. Against a Probabilistic-Deductive Understanding of Support
A second objection targets the notion of one's evidence supporting a
proposition. As I have developed the notion of support above, part of
it is given by some theory of probability. A body of evidence, e,
supports believing some proposition p only if e makes p probable. If
we suppose for simplicity that all of the beliefs that constitute e
are themselves justified, we can say that e supports believing p if
and only if e makes p probable. However, one might argue that, even
with this assumption, one's evidence e can make p probable without one
being justified in believing that p. If this is so, the resulting
evidentialist thesis is false.
Alvin Goldman, for example, has argued that the possession of reasons
that make p probable, all things considered, is not sufficient for p
to be justified (Epistemology and Cognition, 89-93). The crux of the
case he considers is as follows. Suppose that while investigating a
crime a detective has come to know a set of facts. These facts do
establish that it is overwhelmingly likely that Jones has committed
the crime, but it is only an extremely complex statistical argument
that shows this. Perhaps the detective is utterly unable to understand
how the evidence he has gathered supports this proposition. In such a
case, it seems wrong to say that the detective is justified in
believing the proposition, since he does not even have available to
him a way of reasoning from the evidence to the conclusion that Jones
did it. He has no idea how the evidence makes the proposition that
Jones did it likely. Thus, the evidentialist thesis, so understood, is
false.
The appeal to probability and statistics here is not essential to this
sort of objection, so it would be a mistake to focus solely on this
feature of the case in attempting to respond. Richard Feldman has
presented an example which is supposed to demonstrate exactly this
point. His example of the beginning logic student is supposed to show
that being necessitated by one's evidence is not sufficient for one's
evidence to support believing a proposition ("Authoritarian
Epistemology," 150). Feldman asks us to consider a logic student who
is just learning to identify valid arguments. She has learned a set of
rules by which one can distinguish between valid arguments and invalid
arguments, but she has not yet become proficient at applying them to
particular argument forms. She looks at an exercise in her text that
asks her to determine whether some argument forms are valid. She looks
at one problem and comes to believe that it is, indeed, a valid
argument. As the argument is valid, she believes exactly as her
evidence entails she should believe, but she is presently unable to
see how it is that the rules show the argument is, indeed, valid.
Despite her evidence necessitating the proposition that the argument
is valid, it seems she is not justified in believing it.
Various responses are available to the evidentialist. One may here
appeal to the distinction between propositional justification and
doxastic justification in an effort to motivate the claim that the
detective is justified in believing that Jones did it and the student
is justified in believing that the argument is valid. When combined
with a fully developed and well-motivated theory of evidential
support, this may provide a response to these examples. Note, however,
that this reply depends crucially on being able to hold that the logic
student is justified in believing p but not justifiably believing p.
This is a tenuous position, at least for standard accounts of the
basing relation—i.e., for standard accounts of that which, when added
to an instance of propositional justification, yields an instance of
doxastic justification. The dominant view is that the basing relation
is causal, and the student's evidence for believing that the argument
is valid is causing her belief, and it is not doing so in some
non-standard, deviant way. The reply to the objection that appeals to
the distinction between propositional and doxastic justification
demands, therefore, that one also provide a satisfactory account of
the basing relation, and none have so far been formulated.
An alternative response to these examples is simply to accept their
lesson. One might just accept that such examples show that we need to
develop a notion of evidential support that does not appeal solely to
logical relations between one's evidence and those propositions under
consideration. For example, one might hold that one must, in some
sense, grasp or appreciate the logical or probabilistic connection
between one's evidence and the proposition in question in order for
that evidence to support it. Evidentialism allows for such
possibilities.
c. Essential Appeals to Deontology
The view that justification is, in some substantive way, a
deontological concept motivates the following three objections.
According to a deontological conception of epistemic justification,
one has an intellectual duty, requirement, or obligation to believe
justifiably. Deontologists commonly hold that people are rightly
praised for believing or blamed for failing to believe in accordance
with this duty or obligation.
i. Ought Implies Can
Many believe that this deontological conception of epistemic
justification entails that one ought to believe a proposition only if
one can believe it. Put differently, one might think that one has to
be able to believe p in order for one to be justified in believing p.
(This second statement of the issue is more perspicuous, as I here set
aside issues regarding doxastic voluntarism.) Some propositions are
too complicated and complex for a given person to entertain given his
or her actual abilities, and other propositions are too complex for
humans to even possibly entertain. It seems wrong to say that one is
justified in believing that these extremely complex propositions are
true. (EVI), however, appears to imply that one can be justified in
believing such extremely complex propositions, especially given the
theories of evidence and evidential support sketched in section 2d.
above. If, however, (EVI) does have this consequence, then one might
conclude that evidentialism is false.
The argument here has two main premises. The first premise is that
(EVI) entails that one can be justified in believing a proposition
that it is impossible for one to entertain. The second premise is that
if this first premise is true, then (EVI) is false. Because
evidentialism neither rules out nor entails the motivating
deontological conception of epistemic justification, evidentialists
can plausibly deny either premise.
Standard accounts of evidentialism deny the first premise. According
to these accounts, the proper nature of evidential support rules out
the possibility that one's evidence can support a proposition that one
cannot entertain. Evidential support is, in this sense, restricted.
Whether or not such evidentialist theories are acceptable depends
crucially on whether evidentialism is able to accommodate this
restriction in a principled way. Here evidentialists can appeal to
meta-epistemological considerations regarding the nature of epistemic
justification, as well as to intuitions about a sufficiently varied
set of cases. For instance, the deontological conception of
justification itself can motivate and help explain a companion
deontological conception of evidential support. In addition, one can
appeal to cases like Feldman's logic student example (in section 3b.
above) in order to illustrate how the notion of evidential support
should be restricted. Together, these considerations can help to
motivate one's evidentialist theory. In this way, one can formulate a
version of evidentialism that clearly does not have the consequence
that one can be justified in believing a proposition that one cannot
entertain.
By contrast, an evidentialist who rejects a deontological conception
of justification may accept that one can be justified in believing
propositions too complex even to consider and as a result may reject
the second premise of the argument. Again, the theory of evidentialism
itself allows this. This second response to the argument would need to
be strengthened by considerations against the motivating deontological
conception of epistemic justification, but considering these in this
entry would take us too far astray. The crucial point to emphasize
here is that evidentialism neither rules out nor entails this
conception of epistemic justification, so both responses are
consistent with the theory.
ii. An Evidence-Gathering Requirement
Some argue that the justification of a belief depends, at least in
part, on the inquiry that led to the belief. Two ways this can get
fleshed out are as follows. One might argue that only beliefs that
result from "epistemically responsible behavior" can be justified. In
order to be justified on such a view, one must not only follow one's
evidence but also gather evidence in an epistemically responsible way.
Alternatively, one might argue that one is not justified in believing
a proposition if one could have easily discovered (or should have
discovered) evidence that defeated one's present justification for it.
Here, we focus primarily on the latter.
When developing evidentialism in his introductory textbook,
Epistemology, Richard Feldman presents the following example.
A professor and his wife are going to the movies to see Star Wars,
Episode 68. The professor has in his hand today's newspaper which
contains the listings of movies at the theater and their times. He
remembers that yesterday's paper said that Star Wars, Episode 68 was
showing at 8:00. Knowing that movies usually show at the same time
each day, he believes that it is showing today at 8:00 as well. He
does not look in today's paper. When they get to the theater, they
discover that the movie started at 7:30. When they complain at the box
office about the change, they are told that the correct time was
listed in the newspaper today. The professor's wife says that he
should have looked in today's paper and he was not justified in
thinking it started at 8:00. (47)
The professor has good evidence to believe that the movie starts at
8:00, but the claim is that he is not justified in believing this
because he should have (and could have very easily) gathered defeating
evidence. Evidentialism does not take into account one's
evidence-gathering and, thus, cannot account for this intuition.
Evidentialism is a theory about the present justificatory status of
propositions and beliefs for subjects. It provides an account of what
one should now believe, given one's actual situation. Feldman claims
that this is the central epistemological question; it alone determines
the justificatory status of one's beliefs. There are other questions
about when one ought to gather more evidence, but these, Feldman
claims, should be carefully distinguished from questions regarding
epistemic justification (Epistemology, 48). As it is, the professor is
believing exactly as he ought to believe as he is driving to the
theater. As a result, Feldman concludes, evidentialism provides the
correct answer about this case.
iii. Duties Not to Follow One's Evidence
The previous objection to evidentialism attempted to demonstrate that
having evidence that supports believing p is not sufficient for being
justified in believing p. One might also attempt to demonstrate this
by providing examples that do not appeal to evidence gathering
requirements. The following is one such example.
Suppose that Bill comes to possess overwhelming evidence that his
recently deceased wife was having multiple affairs throughout their
marriage. If he were to come to believe what his evidence supports, he
would blame his children and himself. We can further suppose that he
is presently so unstable as a result of his loss that believing that
his wife was having affairs would cause him to seriously harm his
children before committing suicide. In such a case, it is very clear
that Bill ought not to believe that his wife was having affairs.
Indeed, we might say that he has a duty not to believe exactly what
his evidence supports. Since evidentialism implies that he really
ought to believe that his wife was having affairs, evidentialism is
false.
The standard response to these types of examples is to distinguish
between different kinds of demands, oughts, and duties and to hold
that sometimes these conflict. For example, we have an epistemic duty
to follow our evidence, we have a practical duty to not always seek
out more evidence for each of the propositions we consider, and we may
also have moral duties to believe or disbelieve certain propositions.
While these duties can conflict, nevertheless, the epistemic, moral,
and practical demands on us remain. Thus, the response is that Bill
does have an epistemic duty to believe what his evidence supports,
even though he has overriding moral and prudential duties to believe
that his wife was not having affairs. While this response is fairly
uncontroversial, the crucial point to emphasize here is that such a
move is itself a substantial thesis that is in need of support. We
need to be shown in an independently motivated way why we should
believe that matters should be understood in this way rather than in
some other.
d. A Pragmatic Reply
William James has famously argued that having adequate evidence is not
necessary for one to believe justifiably. James notes that our fears,
hopes, and desires (in short, our "passions") do influence what we
believe. We do not proceed in conformance with Clifford's
evidentialist thesis, nor should we. Furthermore, when we are
confronted with an option to do or not to do something, we cannot help
but choose one or the other; the choice is forced. By failing to
decide, we embrace one of the options. In such situations, it can be
permissible for one to believe a proposition in the absence of
sufficient evidence. More specifically, James argues that whenever we
are confronted with a live, forced, momentous option to believe or not
to believe a proposition that cannot be decided on "intellectual
grounds" alone, it is permissible for us to decide on the basis of our
"passional nature" (522).
Consider, for example, the proposition that God exists. Believing or
failing to believe that God exists is a forced and momentous option.
It is forced because we cannot help but choose one or the other; a
failure to decide is, in effect, to choose to not believe that God
exists. It is momentous since it is a unique opportunity to gain
something supremely significant and only one of the options, belief,
will deliver this supreme good. Contrary to the evidentialist, James
argues that one can justifiably believe that God exists in the absence
of supporting evidence if both believing that God exists and failing
to believe that God exists are live options for one.
Here, again, evidentialists can respond by appealing to a distinction
between different kinds of justification. One may be pragmatically or
morally justified in believing against one's evidence, but this is not
to say that one is epistemically justified in so believing. For
example, evidentialists can begin by noting that it is in some sense
very reasonable to let our "passions" influence our actions and
beliefs. It may be in one's own interest to believe that one's wife is
not having an affair, for instance. We might put this point by saying
that one is pragmatically justified in believing that one's wife is
not having an affair. Furthermore, the stakes might be so high that
such pragmatic considerations outweigh any epistemic considerations we
might have. Hence, even though one's evidence does not support
believing p (and one is therefore not epistemically justified in
believing p), it may be, all things considered, more rational for one
to believe p than to not believe p. Of course, nothing here turns on
the content of the belief in question. Similar cases can be
constructed for religious beliefs as well, and some evidentialists
might want to focus on the particular nature of religious beliefs in
order to directly respond to the religious case James considers. In
summary, while it is true that non-epistemic considerations can
outweigh epistemic considerations, the epistemic considerations
remain. While it is not epistemically permissible to flout our
evidentialist duties, we do think that in certain cases it is in some
sense permissible to violate them. In this way, evidentialists can try
to utilize a distinction between different kinds of justification in
order to try to explain away the intuitions that appear to support
James' general thesis, as well as his claims about religious belief in
particular.
e. Rationally Believing Skepticism is False
Keith DeRose has presented a more recent objection that has its roots
in the philosophical challenge posed by skepticism. Two separate
arguments are distinguishable here. First, DeRose argues that
evidentialism appears unable to account for the degree to which he is
justified in believing that particular skeptical scenarios are false
(703-706). The specific argument DeRose presents makes reference to
his contextualist intuitions. In the context of discussing theories of
evidentialism in general, it is important to note this contextualist
dimension of his argument, and I'll make reference to it below.
DeRose thinks people are justified in believing, to a fairly
substantial degree, that they are not brains in vats, and he thinks
that any correct theory of epistemic justification must account for
the substantial degree to which people are so justified in believing.
In order to be an adequate theory of justification, therefore,
evidentialism must show how the evidence people normally possess
substantially supports believing that they are not brains in vats.
DeRose claims that this has not yet been done, and he doubts that
evidentialism can accomplish it adequately.
Second, DeRose claims that this difficulty highlights a fundamental
complexity in the notion of evidence. In short, he thinks that at any
given time we don't have "one simple body of evidence that
constitutes" the evidence that we have (704). For instance, it seems
as though my belief that I have hands is evidence that I have and can
use to support various other propositions—the proposition that I did
not lose them in recent combat, for example. If, though, it is good
evidence that I in fact have and can use, then it seems I should be
able to appeal to it in order to argue that I am not a (handless)
brain in a vat. It seems it should be uncontroversial that one's
evidence justifies one in believing that this skeptical scenario is
false, yet justifying the denial of such skeptical scenarios is much
more difficult than this implies. My belief that I have hands appears
not to be able to justify the proposition that I am not a (handless)
brain in a vat. In summary, when some issues are being discussed, my
belief that I have hands is evidence I can appeal to, but when other
issues are being discussed it appears not to be evidence that I can
use. Evidentialism owes us an explanation of this.
As with most of the objections here considered, the force of DeRose's
points will vary with each proposed version of evidentialism. The
central notions of evidence and evidential support do have to be
explained, and they have to be explained in a way that allows
reasonable conclusions about people's typical appraisals of skeptical
scenarios. As I have developed evidentialism in section 2 above, one
can develop both contextualist and non-contextualist versions. This is
especially important to note because exactly the sorts of
considerations regarding skepticism DeRose invokes motivate
contextualism in general and contextualist versions of evidentialism
in particular. A contextualist version of evidentialism will hold that
when skeptical scenarios are not being discussed, people are justified
in believing to a very high degree that skeptical scenarios do not
obtain. As a result, DeRose's first argument is much more interesting
and intuitively plausible when applied to non-contextualist versions
of evidentialism.
The traditional responses to skepticism are exactly the responses that
non-contextualist evidentialists have available. For example,
non-contextualist evidentialists can utilize some closure principle or
inference to the best explanation to try to account for the degree to
which we think we are justified in believing that skeptical hypotheses
are false. Whether these strategies succeed is controversial, but the
problem of skepticism is a difficult and serious one, and no proposed
solution is uncontroversial. It should be no surprise, then, that one
may object to the consequences any version of evidentialism has for
the skeptical challenge. The fundamental lesson here is that the
evidentialist needs to develop these consequences and defend them.
The second of DeRose's arguments is best understood as a demand for a
fully developed and adequate theory of evidential support. We want to
know how it is that evidence works so as to justify beliefs. This
demand is wholly appropriate, of course, since evidence and evidential
support are concepts central to evidentialism. On one standard
account, I can appeal to the proposition that I have hands in order to
come to believe justifiably that I did not lose them in combat
precisely because I am justified in believing propositions about the
external world (including, of course, the proposition that I have
hands). Although, when one is trying to show how it is that one is
justified in believing that one has hands, one obviously cannot appeal
to the fact that one is justified in believing the proposition that
one has hands. One needs to appeal to other propositions, propositions
whose justification is prior to (or does not depend on) the
justification of the proposition in question. All of this seems to be
uncontroversial, but this is just to explain how evidence works so as
to justify one in believing that certain propositions are true. The
structure of justification is part of evidential support, and it is
because some propositions are more basic than other propositions that
we cannot appeal to those less basic propositions in order to justify
the more basic ones. There is no unclarity here, but the explanation
does help to illustrate why a response to DeRose's first argument is
so crucial. The story depends on one's already being justified in
believing some fundamental external world propositions. It is here
that the evidentialist has to confront the skeptic and somehow explain
how it is that we are justified in believing that skeptical hypotheses
are false.
4. Conclusion
This brief treatment of evidentialism explains it as a type of theory
of epistemic justification. All evidentialist theories are united in
understanding justification as being a function of one's present
evidence as formalized in (EVI), yet many widely divergent options are
available to one who seeks to develop the theory. There are competing
ideas about which mental states count as evidence, different
understandings of the notion of having evidence, various ways of
understanding the crucial notion of support, and also various ways of
relating these three central concepts. Many of the objections
developed above apply only to some of these ways of developing the
theory. This highlights the role they can play in one's attempting to
develop a complete evidentialist thesis. As is the case with theories
in all areas of philosophy, objections such as those developed above
help to guide philosophers towards more promising formulations of the
theory. It remains to be seen whether evidentialism can be formulated
in a way that not only overcomes each of these objections but also
helps us to provide reasonable answers to other central
epistemological questions.
5. References and Further Reading
W. K. Clifford. "The Ethics of Belief." The Theory of Knowledge. 3rd.
ed. Ed. Louis P. Pojman. Belmont, CA: Wadsworth, 2003. 515-518.
Cohen, Stewart. "How to be a Fallibilist." Philosophical Perspectives,
2. Ed. James E. Tomberlin. Atascadero, CA: Ridgeview Publishing Co.,
1988. 91-123.
DeRose, Keith. "Ought We to Follow Our Evidence?" Philosophy and
Phenomenological Research 60 (2000): 697-706.
Feldman, Richard. "Authoritarian Epistemology." Philosophical Topics
23.1 (1995): 147-169.
Feldman, Richard. Epistemology. Upper Saddle River, NJ: Prentice Hall, 2003.
Feldman, Richard and Earl Conee. "Evidentialism." Philosophical
Studies 48 (1985): 15-34.
Goldman, Alvin. Epistemology and Cognition. Cambridge, MA: Harvard
University Press, 1986.
Hume, David. An Enquiry Concerning Human Understanding. 2nd ed. Ed.
Eric Steinberg. Indianapolis, IN: Hackett Publishing Co., 1993.
James, William. "The Will To Believe." The Theory of Knowledge. 3rd.
ed. Ed. Louis P. Pojman. Belmont, CA: Wadsworth, 2003. 519-526.
Plantinga, Alvin. "Reason and Belief in God." Faith and Rationality.
Eds. Alvin Plantinga and Nicholas Wolterstorff. Notre Dame, IN:
University of Notre Dame Press: 1983. 16-93.
Plantinga, Alvin. Warranted Christian Belief. New York: Oxford
University Press, 2000.
Russell, Bertrand. Human Knowledge: Its Scope and Limits. New York:
Simon and Schuster, 1948.
a. More Advanced Studies
While this list in no way approximates comprehensiveness, the
following are some additional helpful works on evidentialism in
epistemology.
Conee, Earl and Richard Feldman. Evidentialism: Essays in
Epistemology. Oxford: Clarendon Press, 2004.
This is, perhaps, the best single work available for exploring
these issues in more detail, and it is by all accounts an excellent
place to start. It includes their article, "Evidentialism," which has
come to be viewed as the definitive article on the theory. It also
contains other previously published articles that not only examine
particular aspects of the theory but also defend favored versions as
well as new, previously unpublished articles on the topic.
Feldman, Richard and Earl Conee. "Internalism Defended." Epistemology:
Internalism and Externalism. Ed. Hilary Kornblith. Malden, MA:
Blackwell Publishers, 2001. 231-260.
Much that has been written on the internalism and externalism
debate in epistemology is very relevant to evidentialism. I choose to
include only one such article here. "Internalism Defended," argues
that evidentialism is one internalist theory of justification that is
able to overcome all of the common objections raised to internalist
theories of justification. Both a version of this paper and an
"afterward" is included in Conee and Feldman's book Evidentialism:
Essays in Epistemology.
Feldman, Richard. "Having Evidence." Philosophical Analysis. Ed. David
Austin. Boston: Kluwer Academic Publishers: 1988. 83-104.
This is a sustained examination of the crucial notion of having
evidence. Feldman demonstrates just how vital it is, clearly lays out
the complications and difficulties involved, and defends one
particular interpretation. Reprinted with an "afterward" in
Evidentialism: Essays in Epistemology.
Haack, Susan. Evidence and Inquiry: Towards Reconstruction in
Epistemology. Cambridge, MA: Blackwell Publishers, 1993.
This is a sustained explication and defense of a novel
evidentialist theory of the structure of epistemic justification.
Haack terms this theory, "foundherentism," as it blends elements of
coherentism and foundationalism. This book is helpful reading for
those who want to gain a more complete understanding of competing
theories of the nature of evidential support.
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