The Interplay Between Knowledge and Truth in Epistemology

What does it mean to know something? At first, this seems like a simple question. But the moment you examine it closely, it opens into one of the deepest and most persistent puzzles in all of philosophy. Knowledge and truth are inseparable – you cannot claim to know something that is false. Yet determining what counts as truth, and how we establish it with sufficient confidence, has occupied philosophers for thousands of years. This is the central problem at the heart of epistemology, and it remains as alive today as it was in ancient Greece.

Knowledge as justified true belief 🔗

The most influential starting point in epistemology is the classical definition of knowledge as justified true belief (JTB). According to this account, for a person to know a proposition, three conditions must be met: the proposition must be true, the person must believe it, and they must have adequate justification for that belief. As OpenStax’s Introduction to Philosophy explains, epistemology describes what knowledge, truth, and justification are – and in doing so, prescribes the proper way to form beliefs. This makes it not just a descriptive discipline but a normative one: it tells us how we ought to think, not just how we do think.

The three-part formula is intuitive. Take the claim “The Earth orbits the Sun.” This is true. Most people believe it. And they have extensive scientific justification for holding the belief. All three conditions are met, and we readily call this knowledge. But philosophers are rarely satisfied with intuitive answers – and it was precisely this formula that came under serious scrutiny in the twentieth century.

What is truth? The major philosophical theories 🔗

For knowledge to exist, truth must first be established. But truth itself is philosophically contested. Epistemic theories of truth attempt to analyze truth in terms of knowledge, belief, justification, and verification – and several distinct schools have emerged over the centuries.

The correspondence theory 🔗

The oldest and most widely held theory is correspondence theory, which holds that a belief or statement is true if and only if it accurately reflects reality. According to the Stanford Encyclopedia of Philosophy, the core idea has been expressed in many ways – through concepts like congruence, agreement, representation, and reference to facts or states of affairs. In everyday terms: the belief that “it is raining” is true if and only if it is, in fact, raining. This theory is closely tied to metaphysical realism – the view that an objective world exists independently of our minds, and our statements either match it or they do not.

The appeal of correspondence theory is obvious: it reflects the common-sense view that truth is not something we invent but something we discover. However, critics point out that it struggles with abstract entities – numbers, moral claims, fictional characters – where the notion of “correspondence to a fact” becomes murky.

The coherence theory 🔗

A significant alternative is the coherence theory, which judges the truth of a belief not by its relationship to external reality but by how well it fits within a broader system of beliefs. As the philosopher F.H. Bradley put it, truth is an ideal expression of the universe that must be internally consistent and comprehensive – a statement is true when it coheres with the whole system of judgments, and false when it does not. Unit 4 of Indira Gandhi National Open University’s philosophy materials notes that the coherence theory emerged partly as a post-Kantian alternative, proposing that the truthfulness of a proposition lies in its logical consistency with other propositions.

A key strength of this view is that it explains how we actually revise beliefs in practice: when new information conflicts with what we already know, we adjust beliefs to restore coherence. The problem, however, is that coherence alone is not sufficient – a completely false but internally consistent set of beliefs could, in principle, qualify as “true” under this theory, with no independent anchor to reality.

The pragmatic theory 🔗

The pragmatic theory of truth, associated with philosophers Charles Peirce, William James, and John Dewey, takes a radically different approach. Rather than asking whether a belief matches reality or fits a system, it asks: does the belief work? The Stanford Encyclopedia of Philosophy explains that pragmatic theories view truth as a function of the practices people engage in when they solve problems, make assertions, or conduct inquiry – true statements are those that are useful to believe, that withstand ongoing examination, or that represent norms of warranted assertibility.

Peirce, for instance, held that a proposition is true if it is the belief that rational inquiry would ultimately converge upon in the long run. James put it more bluntly: truth is what it is expedient for us to believe. This view has been highly influential in the philosophy of science, where theories are evaluated not by perfect correspondence to reality but by their predictive power and practical fruitfulness. The criticism, however, is that it risks relativism – if truth is just what works for a given group, then different communities could have incompatible “truths,” and there would be no neutral standpoint to adjudicate between them.

The intrinsic link between knowledge and truth 🔗

What ties all these theories together is the shared conviction that knowledge requires truth. This is called the factivity of knowledge: you cannot genuinely know something that turns out to be false. The Internet Encyclopedia of Philosophy makes this point sharply: the fact that a belief is justified does not tell us whether it is true or false, and the fact that it is true does not tell us whether it is justified. These are independent conditions – but both are necessary. A justified false belief is not knowledge; a true but unjustified belief is not knowledge either. Only when justification and truth coincide – and do so in the right way – does knowledge arise.

This “right way” requirement is what makes the relationship between knowledge and truth philosophically complex, rather than simply definitional.

The Gettier problem: when justification and truth aren’t enough 🔗

In 1963, American philosopher Edmund Gettier published a short but devastating paper: “Is Justified True Belief Knowledge?” In it, he presented counterexamples showing that a person could have a belief that is both true and fully justified – and still not possess knowledge. According to the Internet Encyclopedia of Philosophy, Gettier problems are situations in which someone has a belief that is true and well supported by evidence, yet which almost all epistemologists agree fails to constitute knowledge.

Consider one of his classic cases: Smith believes that Jones will get a job, based on reliable testimony from their employer. Smith also notices that Jones has ten coins in his pocket. So Smith forms the justified belief: “The person who gets the job has ten coins in their pocket.” As it happens, Smith – not Jones – gets the job. And by sheer coincidence, Smith also has ten coins in his pocket. Smith’s belief is true, and it was justified – but it was true entirely by accident. As the Stanford Encyclopedia of Philosophy notes, a lesson of the Gettier problem is that even true beliefs that are justified can be epistemically lucky in a way that is inconsistent with knowledge.

Wikipedia’s overview of the Gettier problem describes how the paper had a dramatic impact, prompting epistemologists to search afresh for what knowledge truly is. Most agreed that Gettier had refuted the traditional JTB definition, and many proposed adding a “fourth condition” – such as requiring that the justification not rest on any false beliefs, or that the belief be formed through a reliable process – to plug the gap. None of these solutions has been universally accepted, and the Gettier problem remains an open challenge in epistemology.

The role of evidence in affirming truth 🔗

The Gettier problem forces us to think more carefully about what kind of justification counts toward knowledge – and this brings evidence to the center of the discussion. The Stanford Encyclopedia of Philosophy outlines the evidentialist answer: we ought to believe in accord with our evidence. On this view, the strength and reliability of evidence is what separates genuine knowledge from lucky guesses.

But what counts as evidence? Perception is the most immediate form – we see, hear, and touch the world. Testimony extends our reach, allowing us to rely on the knowledge of others. Reason and inference allow us to derive truths that cannot be directly observed. And memory preserves acquired knowledge over time. Epistemologists study all of these sources, examining when each is trustworthy, and under what conditions our reliance on them is justified.

The Gettier problem reveals that evidence alone is not sufficient – it must be appropriately connected to the truth it is meant to support. When a belief turns out to be true only by coincidence, the evidence has done its job in the wrong way. Philosophers have tried to capture this idea through concepts like reliability (the belief-forming process must reliably produce true beliefs), safety (the belief could not easily have been false), and epistemic virtue (knowledge arises when truth is reached through the exercise of intellectual virtues like care, thoroughness, and open-mindedness).

Skepticism and the limits of certainty 🔗

Running through all of these debates is the challenge of philosophical skepticism. Skeptics argue that none of our beliefs is objectively justified as more probably true than its negation – that the search for truth is, in principle, hopeless. As noted in IGNOU’s philosophy unit on theories of truth, even scientists do not label their findings as final or definitive; the proper attitude is to continue searching and remain ready to abandon prevailing beliefs when they are shown to be false.

This is not a counsel of despair but a description of epistemic humility. The goal is not certainty – a bar so high that virtually nothing would qualify – but well-grounded, revisable knowledge. The Internet Encyclopedia of Philosophy captures this tension well: a justified belief will presumably be more likely to be true than an unjustified one, but the exact relationship between justification and truth remains contested. The pursuit of knowledge is, therefore, not a march toward absolute certainty but an ongoing inquiry, shaped by evidence, challenged by counterexamples, and refined through philosophical reflection.

Why this matters beyond philosophy 🔗

These are not merely academic questions. The relationship between knowledge and truth shapes how courts weigh evidence, how scientists design experiments, how journalists verify sources, and how each of us navigates daily decisions. When we ask whether a medical claim is reliable, or whether a news report is accurate, we are implicitly applying epistemological standards – assessing whether the belief is true, whether we are justified in holding it, and whether the evidence genuinely supports the conclusion.

As researchers working across disciplines have noted, philosophical perspectives – including how we define truth and knowledge – directly shape the assumptions underlying research design, interpretation, and the goals of inquiry itself. Epistemology is not separate from life; it is the framework through which all serious inquiry proceeds.

What do you think? If a belief turns out to be true entirely by coincidence – as in Gettier’s examples – should we still count it as knowledge, or does genuine knowledge require something more than truth and justification combined? And given that each major theory of truth (correspondence, coherence, pragmatic) captures something important while leaving something out, is it possible that truth itself is not a single, unified concept but something that looks different depending on the context in which we are asking?

References

1. https://openstax.org/books/introduction-philosophy/pages/7-1-what-epistemology-studies
2. https://en.wikipedia.org/wiki/Epistemic_theories_of_truth
3. https://plato.stanford.edu/entries/truth-correspondence/
4. https://egyankosh.ac.in/bitstream/123456789/38457/1/Unit-4.pdf
5. https://plato.stanford.edu/entries/truth-pragmatic/
6. https://iep.utm.edu/epistemo/
7. https://iep.utm.edu/gettier/
8. https://plato.stanford.edu/entries/knowledge-analysis/
9. https://en.wikipedia.org/wiki/Gettier_problem
10. https://plato.stanford.edu/entries/epistemology/
11. https://en.wikipedia.org/wiki/Epistemology
12. https://i2insights.org/2017/05/02/philosophy-for-interdisciplinarity/