THE EVIDENTIAL SUPPORT RELATION IN EPISTEMOLOGY
1 Introduction
2 Reference Works
3 Evidential Support and Epistemic Goods
4 The Relata of the Evidential Support Relation
5 Probabilistic Accounts of Evidential Support
6 Evidential Support and Epistemic Principles
7 Explanationist Accounts of Evidential Support
8 Causal Accounts of Evidential Support
9 Evidential Support and Higher-Level Requirements
Introduction
Just when does a person’s evidence support a proposition? This question is at the heart of influential
evidentialist views in epistemology, which suggest that at least some epistemically valuable properties are
determined by the relationship between the object of the agent’s attitudes and her evidence. When the
agent adopts an attitude of belief toward some proposition, evidentialists will say that some epistemically
valuable property attaches to that belief just in case the proposition believed is supported by the agent’s
evidence and her belief is properly based on this evidence. A question similar to the one asked above
concerning when evidence confirms a theory has been discussed in the philosophy of science literature.
But, it is not immediately obvious that the notion of evidential support at work in epistemology is the same
as that at work in the philosophy of science literature. The focus of this entry is on debates concerning the
nature of the evidential support relation as it appears in epistemology, especially within evidentialist
views. Among the literature surveyed is literature devoted to the roles the evidential support relation may
play in epistemology, literature concerning the relata of the relation, and literature bearing on the analysis
or partial analysis of the relation. Where appropriate, as in the section *Probabilistic Accounts of
Evidential Support*, literature from the philosophy of science concerning the evidential support or
confirmation of theories will be surveyed as well.
Reference Works
General overviews, textbooks, and reference works on the topic of evidential support in epistemology are
lacking. This is in part because discussion of the topic is at a nascent stage. However, there are some
reference works dedicated to closely related areas which can help acquaint the reader with the topic and
which highlight its importance. Among these are works dedicated to the viability of evidentialist views in
epistemology, works dedicated to the nature of evidence, and works dedicated to the role of evidence in
theory confirmation. In the former category are Plantinga 1998, Feldman 1992, and Mittag 2004. In the
middle category are Kelley 2006 and DiFate 2007. And, in the final category are Hawthorne 2011 and
Kuipers 1998.
DiFate, Victor. “Evidence.” In The Internet Encyclopedia of Philosophy. Edited by James Fieser and
Bradley Dowden. 2007.
Includes large section on the evidential relation mainly devoted to the relation in philosophy of science.
Feldman, Richard. “Evidence.” In A Companion to Epistemology. Edited by Jonathan Dancy and Ernest
Sosa. Cambridge, MA: Blackwell Reference, 1992.
Includes a subsection on evidential support which emphasizes the difficulty of stating precise conditions
under which evidence support a proposition.
Hawthorne, James. “Inductive Logic.” In The Stanford Encyclopedia of Philosophy. Edited by Edward N.
Zalta. 2011.
Discusses evidential support in the context of inductive logic.
Kelley, Thomas. “Evidence.” In The Stanford Encyclopedia of Philosophy. Edited by Edward N. Zalta.
2006.
This article is especially helpful for distinguishing evidence and evidential support in epistemology from
evidence and evidential support in the philosophy of science.
Kuipers, Theo. “Confirmation Theory.” In Routledge Encyclopedia of Philosophy. Edited by Edward Craig.
1998.
Includes a short section on applications of confirmation theory including applications to epistemology.
Mittag, Daniel. “Evidentialism.” In The Internet Encyclopedia of Philosophy. Edited by James Fieser and
Bradley Dowden. 2004.
Includes a short section on support discussing contextualist views of support and degrees of support.
Plantinga, Alvin. “Religion and Epistemology.” In Routledge Encyclopedia of Philosophy. Edited by
Edward Craig. 1998.
Discusses evidentialism and evidential support in the context of religious epistemology. Offers an
argument-based characterization of evidentialism and a probabilistic account of support (following Locke).
Evidential Support and Epistemic Goods
What unites evidentialist views in epistemology is that they analyze epistemic goods, or normative
epistemic properties, at least partially in terms of evidence and evidential relations like the relation of
evidential support. Historical advocates of such views include Hume 1993 and Clifford 2003. Conee and
Feldman 2004 offers a leading contemporary defense of an evidentialist theory of epistemic justification.
Feldman 2000 defends a similar evidentialist account of epistemic obligation. Foley 1987 offers a theory
of egocentric epistemic rationality in terms of a relation of fit, where fit might be partially explicated in
terms of evidential support. Evidentialist theories of epistemic warrant or epistemic permission are
imaginable as well. Further, because it is commonly thought that some epistemic goods are explanatorily
prior to others—that, for instance, epistemic justification is partially constitutive of knowledge (see Gettier
1963) and of understanding (see Kvanvig 2003)—evidentialists are likely to think that the relation of
evidential support plays a key role in the explication of these derivative epistemic goods as well. Of
course, there have been epistemologists who dispute these explanatory priorities, like Audi 1995.
Audi, Robert. “Memorial Justification.” Philosophical Topics. 23.1. (Spring 1995): 31-45.
Argues for internalism about justification but externalism about knowledge thereby permitting the
possibility of unjustified knowledge.
Clifford, William. “The Ethics of Belief.” In The Theory of Knowledge. 3rd ed. Edited by Louis Pojman, 515518. Belmont, CA: Wadsworth, 2003.
This is where Clifford’s remark that “it is wrong always, everywhere and for anyone to believe anything
upon insufficient evidence” is found.
Conee, Earl and Richard Feldman. Evidentialism: Essays in Epistemology. Oxford: Oxford University
Press, 2004.
Includes older and more recent papers explicating and defending their evidentialist theory of justification.
Some of the older papers are followed by an informative afterward.
Feldman, Richard. “The Ethics of Belief.” Philosophy and Phenomenological Research. 60.3 (May 2000):
667-695.
Explicates the concept of a “role” ought and applies it to epistemology. There are obligations which
persons have in their role as believers.
Foley, Richard. The Theory of Epistemic Rationality. Cambridge, MA: Harvard University Press, 1987.
Egocentric rationality, according to Foley, involves fit with one’s deepest epistemic standards. If these
epistemic standards are included among one’s evidence, then rationality is here defined in terms of a
relation with at least some of a person’s evidence.
Gettier, Edmund. “Is Justified True Belief Knowledge?” Analysis. 23.6. (June 1963): 121-123.
Cites other historical advocates of the view that knowledge entails justification.
Hume, David. An Enquiry Concerning Human Understanding. 2nd ed. Edited by Eric Steinberg.
Indianapolis, IN: Hackett, 1993.
Herein Hume makes his famous remark that a wise man “proportions his belief to the evidence.”
Kvanvig, Jonathan. The Value of Knowledge and the Pursuit of Understanding. Cambridge: Cambridge
University Press, 2003.
Argues for a shift in epistemology from focus on knowledge to focus on understanding, where the latter
does not entail the former but does entail justification.
The Relata of the Evidential Support Relation
Since the evidential support relation is a relation, we might ask more specifically what it relates: what are
the relata of this relation? On one side is the evidence and on the other side is what it supports.
Philosophers typically agree that what a person’s evidence supports is a proposition. But, there is a great
deal of disagreement about what constitutes a person’s evidence. Hacking 1975 presents an account of
evidence as consisting in facts which serve as reliable signs or symptoms of something beyond
themselves. Williamson 2000 argues that evidence must consist in known propositions, since only these
play the theoretical roles evidence is supposed to play in various kinds of reasoning. Davidson 1990 had
earlier argued in a similar vein that only something propositional could stand in the sort of explanatory,
probabilistic, and logical relationships in which evidence is supposed to stand. He concluded on this basis
that a person’s evidence consists in propositions she believes. Unmoved by these arguments, Conee and
Feldman 2008 and Pryor 2000 take evidence to consist in mental states, including experiences, since
these play the role these theorists ascribe to evidence in epistemic evaluation. Bonjour 1985 argues that
experiences must be included in one’s evidence. Somewhat more sympathetic with Davidson’s
arguments is McDowell 1996, who agrees that evidence must be able to stand in rational relations but
nonetheless argues that experiences can constitute evidence because of their propositional contents.
Pollock’s 1986 discussion of defeaters for one’s evidence reveals that what is relevant for epistemic
evaluation is whether the agent’s total evidence bears the right relation to the objects of her attitudes.
Some discussions of evidential support nonetheless focus on the question of when individual items of
evidence support propositions, suggesting that the question of when total evidential bodies support
propositions can be answered best by first answering the former question about individual items.
Bonjour, Lawrence. The Structure of Empirical Knowledge. Cambridge, MA: Harvard University Press,
1985.
Develops the “input objection” to show that experiences as well as beliefs must count as evidence.
Conee, Earl and Richard Feldman. “Evidence.” In Epistemology: New Essays. Edited by Quentin Smith,
83-104. Oxford: Oxford University Press, 2008.
Clarifies several key aspects of their evidentialist view, including their concept of evidence.
Davidson, Donald. “A Coherence Theory of Truth and Knowledge.” In Reading Rorty. Edited by Allan
Malachowski. Oxford: Blackwell, 1990.
Davidson’s influential work in semantics is brought to bear in the defense of several coherence theories.
Hacking, Ian. The Emergence of Probability. Cambridge: Cambridge University Press, 1975.
The idea that evidence is constituted by things plays a key role in Hacking’s narration of the story of the
development of modern concepts of probability.
McDowell, John. Mind and World. Cambridge, MA: Harvard University Press, 1996.
Argues that experiences have propositional content and so can stand in rational relationships with beliefs.
Pollock, John. Contemporary Theories of Knowledge. Towata, NJ: Rowman & Littlefield, 1986.
Develops a key distinction between rebutting and undercutting defeaters.
Pryor, James. “The Skeptic and the Dogmatist.” Nous. 34.4. (Dec 2000): 517-549.
Argues for modest foundationalism. Builds on Chisholm’s earlier views.
Williamson, Timothy. Knowledge and Its Limits. Oxford: Oxford University Press, 2000.
This book has been hailed by many as the most important philosophical discussion of the concept of
knowledge in our time. Williamson’s thesis that a person’s evidence is equivalent with what she knows
has received a great deal of attention.
Probabilistic Accounts of Evidential Support
One tempting approach to answering the question of just when a person’s evidence supports a
proposition is to appeal to some kind of probabilistic account. The dominant proposal here is the positive
relevance model, according to which evidence E supports a hypothesis H just in case Pr(H/E) > Pr(H).
Keynes 1973 provides an early proposal like this, suggesting that a distinct kind of probability is required
if the view is to be applicable to epistemology. Fumerton 1995 follows Keynes in this. Carnap provides an
alternative conception. In his 1962, he defends a positive relevance account of confirmation using his
concept of logical probability and argues that substantive bridge principles can be used to connect this
conception of confirmation with epistemology. Swinburne 2001 provides a contemporary example using
such bridge principles to link inductive probability with epistemic probability. Bayesians, like Weatherson
2007, make the connection between confirmation theory and epistemology in part by letting the values for
prior probabilities be determined not by a principle of indifference or some other a priori measure (as in
Carnap) but by the epistemic agent’s degrees of belief. Goodman 1955 and Glymour 1980 offer influential
criticisms of the positive relevance approach. An alternative probabilistic account of support might be
gleaned from reliable indicator theories of knowledge like Alston 1988. Here E’s supporting H is not a
matter of probabilistic relevance but only be a matter of Pr(H/E) exceeding some specified threshold.
Alston, William. “An Internalist Externalism.” Synthese. 74 (March1988): 265-283.
An attempt to use reliable connections between grounds and propositions to explain justification.
Carnap, Rudolf. Logical Foundations of Probability. 2nd ed. Chicago: Chicago University Press, 1962.
Discusses Carnap’s approach to inductive logic as well as bridge principles required to apply this to
epistemology.
Fumerton, Richard. Metaepistemology and Skepticism. Lanham, MD: Rowman & Littlefield, 1995.
Defends an internalist account of justification which makes salient usage of a Keynesian approach to
probability and the direct acquaintance relation.
Glymour, Clark. Theory and Evidence. Princeton: Princeton University Press, 1980.
Presents a canonical account of the “problem of old evidence” for the positive relevance model.
Goodman, Nelson. Fact, Fiction, and Forecast. Cambridge, MA: Harvard University Press, 1955.
Here Goodman first develops his famous “grue” paradox which has often been interpreted as presenting
a challenge to applying the positive relevance model to epistemology.
Keynes, John Maynard. A Treatise on Probability. London: Macmillan, 1973.
First published in 1921. Applies probability even to arithmetic.
Swinburne, Richard. Epistemic Justification. Oxford: Oxford University Press, 2001.
Swinburne argues that a proposition is epistemically probable for a subject when she is disposed to judge
that proposition inductively probable when using the correct criteria for making judgments about inductive
probability.
Weatherson, Brian. “The Bayesian and the Dogmatist.” Proceedings of the Aristotelian Society.107.1.
(August 2007): 169-185.
Defines support in terms of probability relevant to an a priori or informationless background.
Evidential Support and Epistemic Principles
Several epistemologists have attempted to use principles to analyze or partially analyze relations like the
evidential support relation. These principles are taken to be bedrock epistemological truths defeasibly
connecting states of subjects with normative epistemic properties. An example of such a principle would
be: If S is appeared to F-ly, and S has no grounds for doubt, then it is evident to S that something is F.
Such principles are one of the hallmarks of Chisholm’s work in his 1989, where he uses them primarily to
state sufficient conditions for when some claim is reasonable, acceptable, or evident. Van Cleve 1985
and Moser 1985 followed with similar proposals. A related view focusing on seeming states has more
recently been defended by Huemer 2001. One persistent objection to this type of approach is that it is
difficult to see how the advocate of such an approach can rule out in a principled way the claim that, for
instance, an experience of a 23-sided figure supports the proposition that there is a 23-sided figure. Sosa
1988 presents this objection forcefully, while Poston 2007 offers a recent response. A second difficulty for
this principle-based approach, discussed in Pollock 1987, is that the approach has a difficult time
explaining what unifies the various epistemic principles.
Chisholm, Roderick. Theory of Knowledge. 3d ed. Englewood Cliffs, NJ: Prentice Hall, 1989.
Chisholm’s principles form a tightly linked system in which appearances play a fundamental role in
epistemic appraisal.
Huemer, Michael. Skepticism and the Veil of Perception. Lanham, MD: Rowman & Littlefield, 2001.
Defends his phenomenal conservativist principle that seemings provide defeasible justification for their
contents.
Moser, Paul. Empirical Justification. Dordrecht: D. Reidel, 1985.
Offers a more general defense of internalist foundationalism.
Pollock, John. Contemporary Theories of Knowledge. Towata, NJ: Rowman & Littlefield, 1986.
Suggests an analogy between the unity inherent in principles governing bicycle-riding and the unity in
principles governing epistemic practice.
Poston, Ted. “Acquaintance and the Problem of the Speckled Hen.” Philosophical Studies 132 (2007):
331-346.
Argues that states of acquaintance are similar to judgments involving “that is thus.”
Sosa, Ernest. “Beyond Scepticism, to the Best of our Knowledge.” Mind 97.386 (April 1988): 153-188.
Offers an overview of contemporaneous work on the theory of knowledge.
Van Cleve, James. “Epistemic Supervenience and the Circle of Belief.” The Monist. 68.1. (January 1985):
90-104.
Argues that the thesis that epistemic properties supervene on non-epistemic properties supports the
claim that non-doxastic states can evidentially support the contents of doxastic states.
Explanationist Accounts of Evidential Support
An alternative approach to answering the question of just when a person’s evidence supports a claim is to
make use of the concept of explanation. Some philosophers have endorsed a view called explanationism,
according to which a person’s evidence e supports a proposition p just when p is part of the best available
explanation for e. Harman 1986 and Lycan 1988 each present accounts of justification which appeal to
explanatory coherence among one’s beliefs. A proposition p is supported for a subject when it
explanatorily coheres with the contents of her other beliefs. Moser 1989 and Conee and Feldman 2008
offer explanationist accounts of evidential support which permit experiences to qualify as evidence as
well. Lehrer 1974 presents some early problems for explanationist accounts, including examples where a
proposition which is a logical consequence of one’s evidence (and so would seem to be supported by it)
fails to be explanatory of that evidence. The question of whether explanationist accounts can avoid
external world skepticism is addressed by Vogel 1990. Byerly 2012 argues that explanationist accounts
have trouble accounting for justified beliefs about the future.
Byerly, T. Ryan. “Explanationism and Justified Beliefs about the Future.” Erkenntnis online first (April
2012). [doi: 10.1007/s10670-012-9374-7]
Argues that explanationist accounts of evidential support cannot handle certain examples where beliefs
about the future seem well-supported.
Conee, Earl and Richard Feldman. “Evidence.” In Epistemology: New Essays. Edited by Quentin Smith,
83-104. Oxford: Oxford University Press, 2008.
In this work Conee and Feldman for the first time offer an account of evidential support.
Harman, Gilbert. Change in View. Cambridge, MA: MIT Press, 1986.
Uses an explanationist account to defend coherentism.
Lehrer, Keith. Knowledge. Oxford: Oxford University Press.
Offers several important potential counterexamples to explanationist views.
Lycan, William. Judgment and Justification. Cambridge: Cambridge University Press, 1988.
Presents an explanation-based account of justification and contains a treatment of explanatory virtues.
Moser, Paul. Knowledge and Evidence. Cambridge: Cambridge University Press, 1989.
Uses explanationism to account for both justification and knowledge.
Vogel, Jonathan. “Cartesian Skepticism and Inference to the Best Explanation.” Journal of Philosophy
87.11 (November 1990): 658-666.
Classic defense of the idea that our evidence about the external world is best explained by the existence
of such a world.
Causal and Counterfactual Accounts of Support
Instead of using probabilistic relations or explanatory relations (more specifically, those running from the
supported proposition to the supporting evidence) to define evidential support, one might use causal or
counterfactual relations. Roughly, a person’s evidence e supports a proposition p when the right sort of
causal relation connects e with (a state with content) p. Or, e supports p when the counterfactual claim
like if p were false e would not be present is true. Theories like this might be modeled on causal accounts
of knowledge like Goldman 1967 or on related tracking accounts or conclusive reasons accounts of
knowledge like Nozick 1981 or Dretske 1971. In this vein, Swain 1981 offers a reliable causation account
of how a person’s grounds justify her beliefs. One difficulty for such proposals is that they appear to make
the epistemic properties which attach to token attitudes fundamental. Yet, as Kvanvig and Menzel 1990
points out, there are epistemic properties of type attitudes or even of propositions which cannot be
explained adequately in terms of the epistemic properties which attach to token attitudes. Since the
explanation works much more easily the other way around, it is concluded that the epistemic properties
which attach to propositions or type attitudes are more basic than those properties which attach to token
attitudes. This objection could perhaps be circumvented by a proposal which understood a subject’s
evidence to support not by appropriately causing belief but by appropriately causing something short of
belief. Matheson and Rogers 2011 suggest an account along these lines where evidence justifies by
appropriately causing or explaining the presence of non-doxastic seeming states. Byerly 2012 criticizes
such accounts on the basis that seeming states are not sui generis entities.
Byerly, T. Ryan. “It Seems Like There Aren’t Any Seemings.” Philosophia online first (March 2012). [doi:
10.1007/s11406-012-9363-8]
Argues that the main motivations for positing sui generis propositional seeming states fail.
Dretske, Fred. “Conclusive Reasons.” Australasian Journal of Philosophy 49.1 (1971): 1-22.
Dretske argued that knowledge required that if the claim known were not true the believer wouldn’t have
the reasons she did.
Goldman, Alvin. “A Causal Theory of Knowing.” The Journal of Philosophy 64.12 (June 1967): 357-372.
Offers a canonical statement of the causal theory of knowledge, primarily in response to Gettier cases.
Kvanvig, Jonathan and Chris Menzel. “The Basic Notion of Justification.” Philosophical Studies 59.3
(1990): 235-261.
Argues for the view they call “propositionalism,” according to which the kind of justification which attaches
to propositions is most fundamental.
Matheson, Jonathan and Jason Rogers. “Bergman’s Dilemma: Exit Strategies for Internalists.”
Philosophical Studies 152.1 (2011): 55-80.
Paper is focused on providing ways out of a powerful argument against internalist theories of justification
offered by Michael Bergmann.
Nozick, Robert. Philosophical Explorations. Cambridge, MA: Harvard University Press, 1981.
Offers both Nozick’s safety and sensitivity conditions on knowledge.
Swain, Marshall. Reasons and Knowledge. Ithaca, NY: Cornell University Press, 1981.
Offers a reliable indicator theory of justification.
Evidential Support and Higher-Level Requirements
A final frequently discussed question about evidential support has to do with whether the subject must
have any higher-level attitudes or awarenesses of her evidence or of its relation to a proposition in order
for that evidence to support the proposition for her. The first part of the question is very similar to a
question about what it takes to have evidence. In order for evidence to support a proposition for a subject
it is plausible that this evidence must be had by her; but this having relation may well involve an attitude
or awareness concerning the evidence. Feldman 2004 provides a helpful treatment of this issue, arguing
that had evidence is exhausted by currently hosted mental states. Bonjour 1985 suggests, on the other
hand, that in order to have something as evidence, the subject must be aware of it. Bergman 2006
distinguishes two different kinds of awareness—strong and weak. The second part of the question above
is about whether the subject must have some attitude or awareness concerning the relation between her
evidence and a proposition for her evidence to support that proposition. Leite 2008 and Cling 2003 are
among those who have argued that a justified belief that one’s evidence supports p is required for that
evidence to justify the subject’s belief that p. A similar requirement might be made in order for a person’s
evidence to even support p. Tucker 2012 argues that a weaker de re awareness of the relation between
one’s evidence and p is enough. Others, like Greco 2000, argue that no higher-level requirement is
necessary at all. Alston 1980 provides a helpful early discussion of different levels of requirements that
might play key roles in epistemological theorizing.
Alston, William. “Level-Confusions in Epistemology.” Midwest Studies in Philosophy 5.1 (September
1980): 135-150.
This is the classic paper distinguishing different levels of requirements for epistemic properties.
Bergmann, Michael. Justification without Awareness: A Defense of Epistemic Externalism . Oxford: Oxford
University Press, 2006.
Provides influential arguments against internalist views of justification as well as arguments in favor of his
own externalist, proper-function account.
Bonjour, Lawrence. The Structure of Empirical Knowledge. Cambridge, MA: Harvard University Press,
1985.
This suggested can be averred from Bonjour’s discussion of what has become known as the “subject’s
perspective objection” to externalist accounts of epistemic properties.
Cling, Andrew. “Self-Supporting Arguments.” Philosophy and Phenomenal Research 66.2 (March 2003):
279-303.
Defends the idea that in order to gain justification for believing the conclusion of an argument we must
first have justification for believing the principle which connects the premises of the argument to its
conclusion.
Feldman, Richard. “Having Evidence.” In Evidentialism: Essays in Epistemology, ed. Earl Conee and
Richard Feldman. Oxford: Oxford University Press, 2004.
Originally printed in 1988 but is more easily accessible here. Surveys a variety of options for explaining
when a person has evidence before settling on the currently hosted mental state view.
Greco, John. Putting Skeptics in their Place: The Nature of Skeptical Arguments and their Role in
Philosophical Inquiry. Cambridge: Cambridge University Press, 2000.
Greco argues that instead of a higher-level requirement, the believing subject needs to be moved by a
conscientious cognitive disposition of hers from her argument to its conclusion.
Leite, Adam. “Believing One’s Reasons are Good.” Synthese 161.3 (April 2008): 419-441.
Defends a higher-level justified belief requirement for responsible inferential belief.
Tucker, Chris. “Movin’ on Up: Higher-Level Requirements and Inferential Justification.” Philosophical
Studies 157.3 (2012): 323-340.
Discusses a variety of higher-level requirements on inferential justification before settling on either an
acquaintance requirement or a seemings requirement.