Problem of the Criterion

1. Introduction

The Problem of the Criterion is a central puzzle in epistemology and metaphilosophy about how inquiry can get started. It focuses on an apparent deadlock: in order to identify which of our beliefs amount to knowledge or justified belief, we seem to need a criterion of truth or justification; yet in order to establish that criterion as suitable, we seem to need some independently recognized instances of knowledge to test it against.

This tension raises questions not only about individual beliefs but about the structure of epistemic justification as a whole. It has been used to motivate skeptical positions that deny or suspend judgment about our claims to knowledge, as well as non‑skeptical programs that seek to show how knowledge can be grounded despite the problem.

Historically, versions of the problem appeared in ancient Greek skepticism, especially in the works attributed to Sextus Empiricus, where they were deployed against Stoic, Epicurean, and other “dogmatic” schools. Medieval and early modern philosophers reinterpreted the underlying challenge as part of broader projects concerning theological authority, scientific method, and the nature of rational certainty. In the twentieth century, Roderick Chisholm gave the problem its contemporary name and a widely discussed formulation.

The problem has implications beyond traditional epistemology. Analogues arise in debates about:

• what counts as scientific evidence or proper method,
• which sources of religious belief are authoritative,
• and what standards should govern political legitimacy and public reasoning.

Contemporary philosophers propose diverse responses. Some prioritize general methods; others start from particular judgments; some recommend skepticism or suspension of judgment; still others treat the issue as pointing toward holistic or externalist conceptions of justification. No consensus solution has emerged, and the Problem of the Criterion continues to frame fundamental questions about rational belief and the aims of epistemology itself.

2. Definition and Scope

The Problem of the Criterion can be defined, in a standard Chisholmian way, through two interrelated questions:

1. What do we know? (or: Which beliefs are justified?)
2. How are we to decide whether we know? (or: What criterion or method determines justified belief?)

The problem arises because it appears that an answer to either question presupposes an answer to the other. If we start by specifying a criterion (for example, “beliefs formed by reliable perception are justified”), we need prior knowledge that this criterion is correct. If we start from particular putative items of knowledge (for example, “I know I have hands”), we seem to presuppose some underlying standard that licenses counting these as known.

Scope within Epistemology

The problem concerns epistemic justification and knowledge in a very general sense. It is not tied to any single domain (such as perception or testimony) but to the global structure of justification:

• It bears on foundationalism (whether some beliefs can be justified without prior criteria),
• coherentism (whether mutual support among beliefs can supply a criterion),
• and externalism (whether criteria can be grounded in causal or reliability relations outside reflective awareness).

It also interacts with debates about skepticism, since skeptical arguments often exploit the difficulty of providing a non‑circular criterion.

Limits of the Problem

Most discussions distinguish the Problem of the Criterion from:

• Semantic questions about the meaning of “know” or “justified”;
• Psychological questions about how humans in fact form beliefs;
• Purely practical questions about decision or action.

Nonetheless, the problem is sometimes extended to cover practical rationality (what counts as a good decision procedure) and theoretical norms in disciplines such as science, law, and ethics, where analogous issues about starting points and standards arise.

Because the problem is formulated at a high level of generality, it does not dictate any specific metaphysical or scientific outlook; rather, it functions as a structural challenge any theory of knowledge must address.

3. The Core Question of the Criterion

At the heart of the Problem of the Criterion lies the question of priority between standards and instances:

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Should we first identify a criterion of truth or justification, or first identify particular truths or justified beliefs?

This is sometimes described as a dilemma about the starting point of epistemic justification. Attempts to start on either side seem to face difficulties.

The Two Sides of the Priority Question

The core question of the criterion thus asks whether there is a non‑circular, non‑arbitrary way to assign priority or to avoid needing a strict priority at all.

Trilemma and Structural Pressure

Many discussions present the core question as giving rise to a trilemma:

1. Circularity: Justify the criterion by using beliefs already classified as known by that criterion.
2. Infinite regress: Justify each criterion by a further criterion without end.
3. Dogmatic stopping point: Halt the regress without justification at some basic criterion or set of cases.

Proponents of skeptical interpretations argue that every proposed solution seems to fall into one horn of this trilemma. Non‑skeptical responses attempt to reconceive the nature of justification (for example, as holistic, external, or practical) so that the trilemma’s assumptions no longer apply in the same way.

The core question thereby functions as a diagnostic tool: it helps reveal what any theory of knowledge is implicitly assuming about how criteria and cases support one another.

4. Historical Origins in Ancient Skepticism

Ancient Pyrrhonian skeptics, especially as represented by Sextus Empiricus (2nd–3rd century CE), articulated early forms of the Problem of the Criterion in their attacks on dogmatic schools. They questioned whether any proposed criterion of truth—such as reason, sense perception, or certain types of impression—could be justified without circularity or regress.

Sextus Empiricus and the Criterion of Truth

Sextus presents a famous challenge concerning the criterion (kritērion):

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If we judge appearances by a criterion, we shall be judging the criterion itself; and if we judge the criterion, we shall do so by another criterion, and so on ad infinitum.

This is part of a broader argument that any attempt to establish a criterion faces one of three outcomes: circularity, infinite regress, or mere assumption. In Sextus’s presentation, this supports the Pyrrhonian policy of epoché (suspension of judgment):

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Since we are not able to say which is the criterion of truth, we shall not be able to say which of the things presented are true or false either.

Aenesidemus and Modes of Skepticism

Earlier Pyrrhonist Aenesidemus (1st century BCE) is associated with the “ten modes” of skepticism, which aim to show that perceptions and judgments vary in ways that undermine any stable criterion. Although less explicitly focused on the circularity/regress structure, these modes prepare the ground for the later criterion problem by challenging purportedly self‑evident sources of knowledge.

Relation to Other Ancient Debates

The criterion issue emerged in polemics against Stoics, Epicureans, and Academic skeptics:

• Stoics proposed the kataleptic impression (a cognitively “graspable” impression) as a criterion.
• Epicureans appealed to sensations, preconceptions, and feelings as natural standards.
• Academic skeptics, such as Carneades, engaged with but modified earlier criterion debates, emphasizing probabilistic guidance.

Pyrrhonists used the criterion problem to argue against all such positive epistemic programs. Their goal, however, was not to assert a theory of ignorance but to motivate an ongoing suspension of judgment that they associated with tranquility.

5. Dogmatic Responses in Classical Philosophy

In response to skeptical challenges, several classical schools advanced dogmatic (i.e., positive, criterion‑affirming) accounts of knowledge. They typically proposed specific criteria of truth and argued that these were self‑evident, grounded in human nature, or otherwise secure against skeptical attack.

Stoic Epistemology

The Stoics offered one of the most influential ancient criteria: the kataleptic (cognitive) impression. This was an impression said to be:

• caused in the right way by what is,
• stamped and impressed from the object itself,
• and of such a kind as could not arise from what is not.

Stoics held that the wise person can distinguish kataleptic impressions from merely plausible ones and thereby have epistēmē (knowledge). Critics argued that appealing to such impressions as a criterion presupposes the very reliability under dispute, raising issues akin to the later Problem of the Criterion.

Epicurean Accounts

Epicureans defended a more empiricist criterion. They regarded:

• sensations,
• preconceptions (prolēpseis),
• and feelings of pleasure and pain

as natural and incorrigible criteria. Sensations, in particular, were said always to be true as events in the subject, even if the resulting opinions about external objects could be false. Skeptics questioned whether such a view could explain error without undermining the status of sensations as a truth‑criterion.

Aristotelian and Platonic Elements

While Aristotle and later Peripatetics did not formulate the Problem of the Criterion explicitly, they contributed structural ideas:

• Aristotle’s emphasis on first principles known by nous (intellect) provided a proto‑foundationalist picture in which some truths are directly grasped without inference.
• Plato’s discussions of dialectic and recollection suggested that knowledge might have an a priori or rational criterion, though he also acknowledged difficulties about how such knowledge is recognized.

Skeptical Assessment

Skeptics interpreted these dogmatic responses as failing to escape a criterion dilemma: either the criterion is justified by appealing to what it allegedly makes known (circular) or by a further criterion (regress). Dogmatic schools countered that some aspects of human cognition—such as the clear apprehension of certain impressions or first principles—are self‑certifying or manifest, and thus do not require prior validation by independent standards.

6. Medieval Approaches to Knowledge and Authority

Medieval thinkers inherited ancient concerns about knowledge but often embedded them within frameworks centered on theological authority, Aristotelian philosophy, and scholastic method. While they did not usually speak of the “Problem of the Criterion” by name, their views on sources of knowledge and epistemic hierarchies can be read as responses to analogous questions about where justification begins.

Sources and Hierarchies of Knowledge

Medieval philosophers typically distinguished several authoritative sources:

The problem of a criterion appears implicitly in questions about how these sources relate and which has priority in case of conflict.

Thomas Aquinas and the Role of First Principles

Thomas Aquinas defended a broadly Aristotelian foundationalism:

• In natural knowledge, he appealed to self‑evident first principles (such as non‑contradiction) known through intellect.
• In theology, articles of faith revealed by God provided a higher order of certainty than philosophical reasoning.

Aquinas held that certain first principles are known per se and thus do not require validation by a further criterion, softening the impact of any regress problem. Critics and later interpreters debate how far this move addresses the structural concerns highlighted by the Problem of the Criterion.

Other Medieval Positions

• Augustinian traditions emphasized divine illumination, suggesting that the mind’s reliability derives from a direct relation to God. Some view this as positing a transcendental criterion grounded in God’s nature.
• Islamic and Jewish medieval philosophers (e.g., Avicenna, Averroes, Maimonides) similarly combined Aristotelian rationalism with scriptural authority, raising parallel questions about the reconciliation of prophetic revelation with philosophical criteria of truth.

Method and Authority

The scholastic emphasis on disputation and commentary created institutional practices for evaluating claims: appeal to authoritative texts, logical analysis, and consensus among learned doctors. From a criterion perspective, these practices functioned as de facto standards of justification, though medieval authors seldom presented them as needing the kind of non‑circular meta‑justification later demanded by modern epistemology.

7. Early Modern Transformations of the Problem

Early modern philosophers reframed issues underlying the Problem of the Criterion in the context of scientific revolution, religious conflict, and skepticism about inherited authorities. The emphasis shifted toward epistemic method, subjective certainty, and the legitimacy of new empirical science.

Descartes and Methodical Doubt

René Descartes sought a secure starting point for knowledge through methodical doubt. He questioned:

• the reliability of the senses,
• the existence of the external world,
• and even mathematical truths, under the hypothesis of a deceiving God or evil demon.

Descartes’ strategy can be seen as an attempt to solve a criterion problem by finding a belief that is indubitable and thus can function as both starting point and standard. This leads to the cogito (“I think, therefore I am”) and, after arguments for a non‑deceptive God, to the trustworthiness of clear and distinct perceptions. Critics argue that the appeal to God as guarantor of the criterion raises its own circularity concerns.

Empiricism and the Senses as Criterion

Empiricist philosophers, such as John Locke, George Berkeley, and David Hume, elevated experience as the primary source and test of knowledge:

• Locke portrayed the mind as a tabula rasa, with ideas derived from sensation and reflection.
• Hume pressed skeptical worries about induction and causal inference, suggesting that many of our most fundamental beliefs cannot be rationally justified by experience alone.

Empiricism thus proposed sensory experience as a de facto criterion while also exposing the difficulty of justifying that criterion without circularity.

Rationalist Alternatives

Rationalists like Leibniz argued that reason yields necessary truths that cannot be grounded in experience. For them, principles such as non‑contradiction, sufficient reason, and innate ideas functioned as criteria of truth. The question remained how such principles are known and how they apply to the contingent world of experience.

Kant’s Critical Turn

Immanuel Kant reconceived the issue by asking how synthetic a priori knowledge (especially in mathematics and natural science) is possible. Rather than seeking a criterion outside our cognitive faculties, he proposed that the conditions of possible experience—forms of intuition and categories of the understanding—structure all objects as knowable:

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Thoughts without content are empty; intuitions without concepts are blind.

On this view, justification is anchored in the transcendental features of cognition. Some interpreters see this as a way of sidestepping the traditional criterion problem by embedding the “criterion” in the very form of experience, while critics question whether this fully evades regress or circularity at the meta‑level.

8. Chisholm’s Formulation of the Problem of the Criterion

In the twentieth century, Roderick Chisholm gave the Problem of the Criterion its canonical modern formulation, especially in Theory of Knowledge (1966 and later editions). He reframed ancient skeptical concerns in analytic terms and made the problem a central organizing question for epistemology.

Chisholm’s Two Questions

Chisholm posed the problem via two explicit questions:

1. “What do we know?”—a question about the extent of our knowledge.
2. “How are we to decide, in any particular case, whether we know?”—a question about the criteria of knowledge.

He argued that we cannot answer one question without implicitly answering the other. Any attempt to specify a list of known propositions seems to presuppose a standard of selection; any attempt to specify a criterion seems to rely on examples of knowledge used to confirm it.

The Options: Methodism, Particularism, Skepticism

Chisholm identified three main responses:

These categories have since become standard in discussions of the problem.

Chisholm’s Own Stance

Chisholm himself defended a form of particularism combined with internalist foundationalism. He claimed that some commonsense propositions (e.g., “There exists a physical object close to my body”) are more certain than any philosophical theory that would undermine them. From these, he sought to infer epistemic principles.

Critics of Chisholm argue that his selection of “self‑evident” or “more reasonable” propositions is theory‑laden and potentially dogmatic, while sympathizers see his approach as capturing the way ordinary and scientific reasoning in fact proceed.

Chisholm’s clear taxonomy and terminology have influenced much subsequent work, even by authors who reject his preferred solution. The terms “Problem of the Criterion,” “methodism,” and “particularism” are now widely used beyond Chisholm’s own framework.

9. Methodism, Particularism, and Skepticism

The triad of methodism, particularism, and skepticism provides a widely used map of responses to the Problem of the Criterion, especially following Chisholm.

Methodism

Methodists hold that we must first identify an acceptable criterion of knowledge or justification—such as reliable perception, coherence, or scientific method—and then use it to determine which beliefs are justified.

Proponents emphasize:

• the need for explicit standards to avoid arbitrary acceptance of beliefs,
• the promise of a systematic and uniform approach.

Critics contend that methodism struggles to justify its initial criterion without circular appeal to beliefs already favored by that standard or without an unending regress of higher‑order criteria. Some also say that it misdescribes ordinary epistemic practice, in which people generally do not explicitly adopt a criterion before knowing many things.

Particularism

Particularists begin from some allegedly obvious or commonsense cases of knowledge (e.g., that there are external objects, that memory often works) and then work backward to articulate principles that accommodate these cases.

Advantages claimed include:

• alignment with common sense and everyday certainty,
• avoidance of regress by taking some judgments as epistemically privileged starting points.

Objections focus on worries about dogmatism and question‑begging: skeptics challenge whether there are any uncontroversial knowledge‑claims to serve as starting points, and others argue that the choice of “clear” cases may secretly rely on background methodological assumptions.

Skepticism about the Criterion

Skeptics maintain that neither methodism nor particularism can non‑question‑beggingly justify the relationship between criteria and instances. This leads some to:

• withhold assent about what, if anything, is known (a Pyrrhonian stance),
• or assert that knowledge is impossible (more radical forms).

Skeptical positions often stress the force of the regress/circularity dilemma and treat proposed solutions as resting on arbitrary stopping points.

Variants and Hybrids

Some contemporary philosophers propose hybrid or alternative stances:

• Holistic or reflective equilibrium approaches (sometimes seen as a sophisticated form of particularism or as transcending the dichotomy),
• Contextualist accounts that vary standards across conversational contexts,
• Externalist views that treat reliability or proper function as criteria not requiring reflective endorsement.

Debate continues over whether these alternatives genuinely escape the original trilemma or merely redescribe its terms.

10. Foundationalism, Coherentism, and Regress

The Problem of the Criterion intersects closely with debates about the structure of justification, particularly between foundationalism and coherentism, and with the issue of infinite regress.

The Regress Problem

The classical regress of justification can be framed as follows:

1. A belief is justified only if supported by another justified belief.
2. This supporting belief itself requires justification, and so on.

This appears to yield three options:

The criterion problem can be seen as a higher‑order version of this regress, asking how we justify the principles that govern these relations.

Foundationalism

Foundationalists posit basic beliefs that are justified non‑inferentially (for example, self‑evident truths, perceptual seemings, or simple memory beliefs). These then support non‑basic beliefs via epistemic principles.

Different foundationalists offer different candidates for basic status:

• Classical views favor incorrigible or infallible beliefs (e.g., Descartes on clear and distinct perceptions).
• Moderate or fallibilist foundationalists allow basic beliefs to be defeasible yet initially justified.

From a criterion perspective, basic beliefs often serve as anchors: they are taken to be known without prior application of a criterion, thereby limiting regress. Critics argue that foundationalism either smuggles in criteria at the ground level (making it vulnerable to the original problem) or leaves basic beliefs unjustified in a way that seems arbitrary.

Coherentism

Coherentists deny that justification requires foundational beliefs. Instead, a belief is justified if it belongs to a coherent system—mutually supporting and free from internal contradiction.

On this view, there is no single privileged starting point; justification emerges from global coherence among beliefs, including perceptual reports, memories, and theoretical principles. Some coherentists, especially in ethics, develop this through reflective equilibrium, where principles and judgments are iteratively adjusted.

Applied to the criterion issue, coherentism suggests that:

• criteria and instances of knowledge support each other holistically,
• the demand for a one‑way priority between them is misguided.

Critics question whether mere coherence can connect belief systems reliably to reality and argue that coherentism may still presuppose some notion of evidential fit that functions as an implicit criterion.

Alternative Structures

Other structural proposals—such as infinitism (endorsing an infinite but non‑vicious regress of reasons) and hybrid views (foundherentism, foundational‑coherentist mixes)—offer further attempts to address regress and thereby influence approaches to the Problem of the Criterion, though their direct implications are debated.

11. Contemporary Externalist and Pragmatist Responses

Contemporary epistemology includes influential externalist and pragmatist approaches that reinterpret or downplay the Problem of the Criterion by altering assumptions about justification, knowledge, or the aims of epistemology.

Externalist Approaches

Externalism holds that factors outside a subject’s reflective access—such as the reliability of cognitive processes or their proper function—can suffice for knowledge or justification. Prominent forms include:

• Reliabilism (e.g., Alvin Goldman): a belief is justified if produced by a reliable process.
• Proper functionalism (e.g., Alvin Plantinga): knowledge involves cognitive faculties functioning properly in an appropriate environment according to a design plan.

From this perspective, the need for a consciously adopted criterion is reduced. The relevant “criterion” may consist in objective reliability or design, not in a rule the agent must justify from within.

Supporters argue that:

• everyday and scientific knowledge do not typically involve resolving the meta‑level criterion problem;
• externalist conditions allow knowledge even when agents lack a non‑circular defense of their methods.

Critics counter that externalism may leave reflective justification unaddressed: even if knowledge is externally grounded, the internal question “How do we know that this is a good method?” appears to persist.

Pragmatist Responses

Pragmatist thinkers (e.g., Charles Peirce, William James, John Dewey, and, in a different register, Hilary Putnam and C.S. Peirce’s successors) tend to reconceive epistemic norms in terms of inquiry, practice, and success.

Key themes include:

• Criteria are justified insofar as they work in guiding successful inquiry over time.
• The demand for ultimate, non‑circular foundations is replaced by a focus on fallible but self‑correcting methods.
• Communities of inquirers, rather than isolated individuals, are central.

Peirce, for instance, links the justification of methods to the long‑run convergence of inquiry:

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The opinion which is fated to be ultimately agreed to by all who investigate is what we mean by the truth.

On such views, the Problem of the Criterion is sometimes seen as arising from an overly static picture of knowledge. Instead of asking for a foundational criterion, pragmatists ask which practices best promote stable, fruitful belief in the long run.

Critics argue that pragmatic success does not straightforwardly entail truth and that appealing to what “works” may smuggle in background criteria (such as predictive accuracy or explanatory power) that themselves call for justification.

Contextual, Naturalized, and Deflationary Tendencies

Related strands include:

• Contextualism, which treats epistemic standards as varying with conversational or practical context, potentially softening the demand for a single universal criterion.
• Naturalized epistemology (e.g., Quine), which replaces normative questions about justification with empirical study of cognitive processes and their success in prediction and control.
• More deflationary views that regard the search for a global criterion as misguided or conceptually confused.

These approaches often diminish the prominence of the Problem of the Criterion without necessarily solving it in the traditional sense.

12. Intersections with Science and Methodology

The Problem of the Criterion has clear analogues in debates about scientific method and evidence. Scientists and philosophers of science must decide which procedures, instruments, and inferential rules count as reliable without presupposing, in a circular way, the very successes they are meant to explain.

Scientific Standards and their Justification

Questions include:

• What counts as acceptable evidence?
• Which experimental designs (e.g., randomized controlled trials) are methodologically sound?
• How should we evaluate theory choice (e.g., via simplicity, explanatory power, predictive success)?

These can be framed as criterion questions: they ask for standards by which scientific claims are judged.

Attempts to justify scientific methods sometimes appeal to past successes of science, leading critics to worry about circularity: science is vindicated by its results, which are taken as reliable because of the methods used to produce them.

Philosophical Responses

Different philosophies of science respond in ways parallel to epistemological positions:

• Logical empiricists tried to codify a formal criterion (e.g., verifiability), facing well‑known difficulties.
• Critical rationalists (e.g., Karl Popper) emphasized falsifiability as a demarcation criterion, while acknowledging that no method can be justified with absolute certainty.
• Kuhn, Lakatos, and Feyerabend highlighted the historical and sociological dimensions of scientific change, suggesting that actual scientific criteria are evolving, paradigm‑dependent, or pluralistic.

Some naturalized epistemologists argue that empirical study of which methods in fact yield successful prediction and control is the appropriate way to address criterion‑like concerns, rather than seeking a priori justification.

Methodological Pluralism and Practice

Contemporary philosophy of science often endorses a form of methodological pluralism, recognizing:

• different evidential standards across disciplines (e.g., physics vs. epidemiology),
• and context‑dependent trade‑offs (e.g., between internal and external validity).

From a criterion standpoint, this pluralism suggests that there may be no single, universal scientific criterion, but rather a family of practices whose justification is partly pragmatic, partly historical, and partly normative. The extent to which this pluralism resolves or simply relocates the Problem of the Criterion remains contested.

13. Religious Epistemology and Competing Criteria

In religious epistemology, the Problem of the Criterion appears in disputes over which sources and standards legitimately ground religious belief. Competing traditions and secular perspectives offer different answers to questions such as: What counts as a reliable route to knowledge of the divine, if any?

Sources of Religious Belief

Commonly proposed epistemic sources in religion include:

The criterion problem arises when these sources conflict (across or within traditions) or when their authority is itself in question.

Internalist and Externalist Religious Epistemologies

Some religious epistemologists adopt internalist approaches, demanding that believers be able to articulate reasons for treating certain sources as authoritative. For example:

• Classical natural theology attempts to show, by argument, that a theistic worldview is more reasonable overall, thereby indirectly supporting scriptural or experiential criteria.

Others embrace more externalist or reformed epistemology perspectives (e.g., Alvin Plantinga), holding that belief in God can be properly basic when formed by a sensus divinitatis, and that no prior criterion‑justification is necessary for rationality.

Critics of reformed epistemology question whether treating certain religious beliefs as criterion‑independent basics is epistemically symmetric with secular or rival religious claims, raising worries about arbitrariness familiar from the general Problem of the Criterion.

Inter‑Religious and Secular Disagreement

Plurality of religions and worldviews intensifies criterion issues:

• Different traditions may regard distinct scriptures or revelations as ultimate standards.
• Secular viewpoints may reject revelation as a criterion, insisting on publicly accessible evidence or universal reason.

Discussions about religious diversity thus often focus on meta‑criteria: what counts as a fair or neutral standard for adjudicating between conflicting claims? Some argue that no fully neutral criterion is available; others propose minimalist criteria (e.g., non‑contradiction, coherence with basic empirical facts) as common ground.

Pragmatic and Fideist Tendencies

Some responses emphasize pragmatic considerations: religious frameworks are evaluated by their existential, moral, or communal fruits rather than by a single evidential criterion. Fideist positions go further, treating faith as independent of, or even opposed to, standard epistemic criteria, thereby sidestepping the problem at the cost of loosening the link between religious belief and knowledge‑claims.

These varied approaches illustrate how the Problem of the Criterion underlies many disputes about rationality, justification, and authority in religious contexts.

14. Political Legitimacy and Epistemic Standards

In political theory and practice, analogues of the Problem of the Criterion arise in questions about legitimacy, authority, and public reasoning. Societies must choose standards by which to judge laws, institutions, and policies, yet those standards are themselves contested.

Criteria of Political Legitimacy

Potential criteria include:

Disagreement often concerns which of these criteria should be primary, and how they are themselves justified.

Epistemic Standards in Public Deliberation

Modern democracies rely on shared epistemic norms to guide policy debates:

• What counts as valid evidence (e.g., scientific studies vs. anecdote)?
• Which experts or institutions are trustworthy?
• How should testimony, statistics, and risk assessments be evaluated?

These questions mirror the general criterion problem: participants must endorse some standards for credible information and rational argument, yet justifications for these standards may depend on contested worldviews or institutions.

Liberalism, Public Reason, and Meta‑Criteria

Theories of public reason (e.g., John Rawls) attempt to address this by proposing meta‑criteria for acceptable political justification in pluralistic societies:

• Appeals should be made in terms that all “reasonable” citizens could in principle endorse.
• Political decisions should be justifiable by public reasons rather than sectarian doctrines.

Such proposals themselves invite criterion questions: who counts as “reasonable,” and by what standard? Critics argue that public reason frameworks may smuggle in substantive liberal values as if they were procedural criteria.

Epistemic Democracy and Expertise

Debates about epistemic democracy focus on whether democratic procedures track truth or justice better than alternatives:

• Some argue that inclusive deliberation and majority rule have epistemic virtues (e.g., aggregating dispersed information).
• Others emphasize the need for epistemic authorities or technocratic input.

The challenge is to specify criteria for when to defer to experts, how to balance expertise with participation, and how to maintain legitimacy when citizens challenge the criteria used to evaluate evidence and argument.

These discussions reveal how criterion‑like questions permeate political life, where disagreements about what counts as knowledge or good reasoning can shape institutional design and public trust.

15. Ongoing Debates and Unresolved Issues

Despite extensive historical and contemporary work, the Problem of the Criterion remains a subject of active debate. Several unresolved issues structure current discussions.

Is the Problem Inevitable or Ill‑Formed?

Some philosophers argue that the problem reveals a deep feature of rational evaluation and cannot be dissolved. Others contend that it rests on questionable assumptions—for example:

• that justification must be reflectively accessible,
• that standards must be global and invariant,
• or that there must be a strict priority relation between criteria and instances.

Disagreement persists over whether revisions to these assumptions genuinely remove the problem or merely postpone it.

The Status of Common Sense

Particularist and common sense realist approaches continue to debate skeptics and revisionists about:

• whether certain beliefs (e.g., about the external world or other minds) can be treated as epistemically privileged,
• how to explain their special status without circularity or arbitrariness.

Some propose virtue epistemology—focusing on intellectual character traits—as a way to ground trust in our faculties, while critics regard this as shifting the criterion question rather than solving it.

Externalism vs. Internal Reflection

The tension between externalist and internalist responses remains significant. Key questions include:

• whether external conditions (reliability, proper function) suffice for knowledge when the agent cannot justify any criterion,
• and whether epistemology should prioritize truth‑conducive processes or reflective rationality.

This shapes how pressing the Problem of the Criterion is taken to be: externalists often see it as less threatening, internalists as more central.

Holism, Coherence, and Reflective Equilibrium

Holistic approaches that appeal to coherence or reflective equilibrium are influential, yet contested:

• Supporters argue they best capture real‑world theory choice in science, ethics, and everyday life.
• Critics question whether such approaches provide independent reasons for trust in the resulting belief systems.

The meta‑question—why a coherent or equilibrated system should count as justified—remains a recurring focus.

Cross‑Domain and Interdisciplinary Perspectives

Intersections with science, religion, and politics highlight the diversity of practical responses to criterion‑like problems. Whether a unified philosophical treatment can accommodate this diversity, or whether domain‑specific accounts are preferable, is an ongoing point of contention.

Overall, the literature exhibits no convergence on a definitive solution, and many see the Problem of the Criterion as a continuing lens through which to analyze broader epistemological and methodological disputes.

16. Legacy and Historical Significance

The Problem of the Criterion has had a lasting impact on both epistemology and metaphilosophy, shaping how philosophers conceive the aims, methods, and starting points of inquiry.

Influence on Skepticism and Anti‑Skepticism

Historically, the problem supplied a key tool for skeptical traditions, from ancient Pyrrhonism through early modern doubts to contemporary skepticism. At the same time, attempts to respond to it have motivated:

• foundationalist projects seeking secure starting points,
• common sense and pragmatic defenses of ordinary belief,
• and externalist redefinitions of knowledge.

Thus the problem sits at the center of debates about whether skepticism can be answered and what such an answer would require.

Structuring Epistemological Theories

Modern epistemology often organizes itself around options that emerged or were clarified through criterion discussions:

• methodism vs. particularism and variants,
• foundationalism, coherentism, and hybrids,
• internalism vs. externalism.

By foregrounding questions about where to begin and what counts as evidence or justification, the Problem of the Criterion has encouraged more explicit reflection on the meta‑level assumptions of epistemic theories.

Broader Intellectual and Cultural Effects

In science, religion, and politics, criterion‑like worries contribute to:

• skepticism toward traditional authorities,
• calls for explicit methodological norms,
• and awareness of the potential circularity in appeals to “what works” or “what everyone knows.”

These concerns have informed modern ideals of critical reflection, transparency, and justification in public discourse and institutional design.

Metaphilosophical Significance

The problem also raises questions about the nature of philosophy itself:

• whether philosophy can provide foundational criteria for knowledge,
• or whether it is better seen as a practice of conceptual clarification, therapy, or reflective articulation of existing norms.

Some traditions treat the persistence of the Problem of the Criterion as evidence of the limits of philosophical theorizing; others view it as an enduring reminder of the need for humility, pluralism, and self‑critique in epistemic enterprises.

Through these roles, the Problem of the Criterion has helped shape the self‑understanding of philosophy across historical periods and continues to frame discussions of what it means to know, to justify, and to reason responsibly.