

The Core Theme - Knowledge and the Knower
Lesson 2 - What is Knowledge? (Scope 2)
Everyone assumes they know what knowledge is. Philosophers have spent 2,500 years discovering that the answer is far harder than it looks.
THE PROVOCATION
Two schools, two ideas of knowledge
Is knowledge something you accumulate, or something you do? The answer shapes everything about how a school teaches you.
"To stress process at the expense of factual knowledge
actually hinders children from learning to learn."
E.D. Hirsch, "You can always look it up... or can you?" (2000)
There is a debate in education right now, one you may have experienced without knowing it had a name. On one side: the knowledge-rich curriculum and on the other side: the skills-based curriculum.
The knowledge rich argument for education is that students cannot think critically, analyse, or reason effectively without a rich store of factual knowledge in memory. Skills rest on knowledge. You cannot evaluate an argument about the French Revolution if you do not know what the French Revolution was. You cannot read critically if your vocabulary is thin. I made a short film about this a few years ago.
The skills-based education argument is that in a world of instant information access, what matters is not what you know but what you can do with information. Memorising facts is the wrong goal. Teach students to search, evaluate, synthesise, create. The skill of critical thinking transfers across contexts. Knowledge, in this view, is what you look up, not what you carry.
My students who do the IB with the Swiss Maturité are right in the middle of this debate.
The Swiss Maturité leans toward the knowledge-rich tradition: lots of content, sustained study of traditional texts and methods, high expectations of factual recall. The IB leans toward the skills-based tradition: approaches to learning (ATLs), self-directed inquiry, transferable competencies. The fact that you have experienced both gives you something most people in this debate do not have: an insider’s perspective.
But before we can decide who wins that debate, we have to answer a more basic question: What is knowledge? Not what does it feel like, not what do schools call it, but what actually makes something knowledge rather than mere belief, opinion, or information? That is the question TOK is built around. And philosophers have been arguing about it for 2,500 years.
Four big ideas are covered in what follows. First, Plato's answer to the knowledge question, Justified True Belief, the standard for over two thousand years. Secondly, Edmund Gettier's challenge to JTB, which took all of three pages in the 1960s. Thirdly, the distinctions French, German, Spanish and Italian already hand you - savoir and connaître, Wissen and Kennen - for something English never bothered to name. And finally, whether the whole knowledge-versus-skills debate this lesson opened with was ever asking the right question.
Traditional vs Progressive Education
Seah Seng Wee and NotebookLM.
This video generated with the help of AI outlines the key features of traditional and progressive education and concludes with an argument that is best to do both if you can!
Four big ideas about the nature of knowledge.
Big idea 1 - The classic answer: Justified True Belief
What would make a belief something more than a belief? What would make it knowledge?
"True opinions are a fine thing and do all sorts of good so long as they stay in their place; but they will not stay long. They run away from a man’s mind, so they are not worth much until you tether them by working out the reason." - Plato, Meno, trans. G.M.A. Grube.
Philosophy’s standard answer to “What is knowledge?” was, for most of its history, both elegant and compelling. Knowledge, the tradition held, is belief that is true, and that you have good reason to hold. In the language philosophers use: knowledge is Justified True Belief, or JTB. The three conditions are each necessary, and together they were thought to be sufficient.
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Belief: you must actually hold the proposition, you cannot know something you have never considered.
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Truth: the proposition must correspond to reality, you cannot know something false.
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Justification: you must have adequate grounds for your belief, a lucky guess, even if correct, does not count as knowledge.
Consider two situations. In the first, you watch Wales beat France in the rugby Six Nations. You believe Wales won, your belief is true, and you have a reliable basis for it - you saw it happen. JTB says you know Wales won. In the second, you missed the match and a friend - someone who never watches rugby and was guessing - texts to say Wales won. They happen to be right. Your belief is still true. But the source is not reliable, and the fact that your friend guessed correctly this time was luck. JTB says you do not know Wales won - not because you had no reason for your belief, but because the reason was not the kind that connects beliefs to truth reliably. Justification, on this account, is not just any reason for believing something. It is a reason that is epistemically trustworthy - one that tends to produce true beliefs because it is tracking something real.
This thinking process goes all the waa back to Plato. In the Meno, Plato uses the image of statues of Daedalus that walk away unless you tie them down. True beliefs, he says, are like those statues: they are valuable only when fastened by reasoning. In the Theaetetus, Plato works through the problem more systematically, testing and eventually rejecting several candidate definitions of knowledge before arriving at something close to JTB. For roughly 2,400 years after Plato, Western philosophy treated JTB not as one possible answer but as the answer.
The philosophical vocabulary that comes with JTB matters beyond this lesson. The propositional knowledge, “knowing that” we identified last lesson is the territory JTB is designed to map. When you claim to know that the Battle of Hastings was in 1066, that climate change is human-caused, that Wales won the Six Nations in 2019: these are propositional knowledge claims, and JTB sets out what makes them genuine knowledge rather than mere belief. Keep that vocabulary, you will need it throughout the course.
JTB and Gettier
CrashCourse
In this cat rich episode Hank Green talks about some philosophy stuff, like a few of the key concepts philosophers use when discussing belief and knowledge: what defines an assertion and a proposition, and that belief is a kind of propositional attitude. Hank also discusses forms of justification and the traditional definition of knowledge, and introduces us to Edmund Gettier. Worth the detour.
Big idea 2 - The crack in the foundation: Gettier
Can you have a justified true belief that is not knowledge?
"...it is possible for a person to be justified in believing a proposition that is in fact false"
Edmund Gettier, "Is Justified True Belief Knowledge?" (1963)
In 1963, a philosopher named Edmund Gettier published a paper three pages long. He was thirty-five years old and, by his own account, did not think it was much of an essay. He almost did not publish it. He submitted it mainly to have something on his CV. The paper was called "Is Justified True Belief Knowledge?" and it changed philosophy.
Gettier's method was simple: he constructed cases where all three conditions of JTB are met - belief, truth, justification - and yet something has clearly gone wrong. The subject does not seem to know anything. The cases are brief, almost conversational, but their implications for JTB were significant.
Case One: The Job and the Coins
Smith and Jones have both applied for the same job. Smith has strong evidence - the company president told him directly - that Jones will get the job. Smith also knows that Jones has exactly ten coins in his pocket; he counted them himself ten minutes earlier. Smith therefore forms the justified belief: "The man who will get the job has ten coins in his pocket."
As it turns out, Smith gets the job, not Jones. And, by a coincidence Smith had no way of knowing about, Smith also has exactly ten coins in his own pocket. So the proposition "The man who will get the job has ten coins in his pocket" is true. Smith believed it. Smith was justified in believing it. But Smith did not know it - his belief was grounded in facts about Jones, and the proposition turned out to be true for reasons entirely unconnected to Jones.
Case Two: The Ford and Barcelona
Smith has strong evidence that his friend Jones owns a Ford. Jones has always driven a Ford, has just been seen driving one, and has offered Smith a lift in it. Smith therefore forms the justified belief: "Jones owns a Ford." He then constructs three further beliefs by logical addition, picking three city names at random: either Jones owns a Ford, or Brown is in Boston; either Jones owns a Ford, or Brown is in Barcelona; either Jones owns a Ford, or Brown is in Brest-Litovsk. Each is logically entailed by the first belief, so if "Jones owns a Ford" is justified, all three are too.
As it turns out, Jones does not own a Ford - he was driving a rental car. But Brown, completely by coincidence, really is in Barcelona. So "Either Jones owns a Ford or Brown is in Barcelona" is true. Smith believed it. Smith was justified in believing it. But Smith did not know it - the proposition is true for a reason Smith had no access to, and the belief is true entirely by accident.
Both cases share the same structure. Justification and truth are both present, but they come apart: the justification points in one direction, and the truth arrives from somewhere else. Gettier's conclusion is stark: JTB is not sufficient for knowledge. Something is missing. What that missing ingredient is has occupied epistemologists ever since.

Big idea 3 - The map of knowledge
You are already multilingual. Your French already knows more about knowledge than English does.
"The man who has no tincture of philosophy goes through life imprisoned in the prejudices derived from common sense, from the habitual beliefs of his age or his nation, and from convictions which have grown up in his mind without the co-operation or consent of his deliberate reason." Bertrand Russell, The Problems of Philosophy
You have an advantage in this lesson that most anglophone TOK students do not have: you also speak French and German. In French you have two words for 'to know': savoir et connaître. You know that to translate "to know" in German: you have Wissen and Kennen. And you might also know that Italian has sapere and conoscere and that Spanish has saber and conocer. Every major European language except English encodes, in its most basic vocabulary, a distinction that philosophers took centuries to articulate in analytical terms. If you have ever felt that something was lost in translation when you switched from French to English - that a sentence "knew" something in French that it could not quite say in English - this is often why. What English calls "knowing" turns out to cover very different things. That is what this section maps out.
Je connais, je sais et je suis.
In French, to know that Paris is in France and to know Paris are not the same verb. "Je sais que Paris est en France" - savoir: to know a fact, a proposition, something that can be stated and verified. "Je connais Paris" - connaître: to know a city, a person, a piece of music, by direct experience and acquaintance. Two different relationships with the world, two different verbs. English collapsed them into one word sometime in the medieval period, and anglophone epistemology has been trying to reconstruct the distinction ever since.
The philosopher Bertrand Russell formalised the savoir/connaître distinction in English. He called it knowledge by acquaintance and knowledge by description. Knowledge by acquaintance is direct, immediate contact with something - the redness of a sunset as you actually see it, the taste of coffee as you drink it, the texture of a city you have lived in. No description can fully substitute for acquaintance. Knowledge by description is indirect: it is knowing that something has certain properties, often without direct experience of it. You can know, by description, that the tallest mountain on Earth is 8,849 metres high without ever having seen Everest. Your friend in Australia can know, by description, that Geneva is a typical Swiss city without travelling here. Russell's point: connaître tracks acquaintance; savoir tracks description. Your French had already done the philosophy.
A related distinction, rooted in the work of another English philosopher Gilbert Ryle, separates propositional knowledge ("knowing that") from procedural knowledge ("knowing how"). In The Concept of Mind (1949), Ryle argued that the Cartesian picture of a mind-ghost operating a mechanical body generates a systematic error: the assumption that all knowledge is ultimately a kind of inner knowing-that, a proposition held in the mind. But knowing how to ride a bicycle is not a set of propositions about balance and pedalling. Expert cyclists cannot articulate what they know. The knowledge lives in the body, in trained patterns of response. It is procedural rather than propositional. This is the same idea that I used Polanyi to open with in Lesson 1: he called it tacit knowledge, 'we know more than we can tell.' Ryle and Polanyi were working on the same problem within a decade of each other - Ryle dismantling a philosophical picture of the mind, Polanyi describing how science actually gets done - and they converged on the same example because the example is unusually hard to escape.
This distinction also matters enormously for the education debate you were asked to think about at the start of this lesson. "Critical thinking" cannot be taught as a pure skill because there is no such thing as context-free critical thinking: it always requires propositional knowledge, knowledge of the domain you are thinking about. The skills advocate's response might be that procedural knowledge - the habit of mind, the practice of evaluation - genuinely transfers across domains in a way that propositional knowledge does not. Both sides of the debate need this vocabulary to have an effective argument.
A further distinction runs through both everyday language and philosophical argument: knowledge versus belief versus opinion versus information. These are not synonyms. Information is data, a raw signal that may or may not be true and that does not, on its own, constitute knowledge. Belief is any proposition you hold to be true, regardless of whether it is true or justified. Opinion is usually a belief about a contested matter where the grounds are disputed. Knowledge, on the Justified True Belief account, requires all three conditions. Keeping these distinctions clear is the basic equipment for thinking carefully about what you know and how you know it.
Big idea 4 - The knowledge v skills debate is asking the wrong question
Is knowledge-rich versus skills-based even the right fight?
"We are now a culture whose information, ideas and epistemology are given form by television, not by the printed word." Neil Postman, Amusing Ourselves to Death
The Gettier problem showed that knowledge is harder to define than anyone thought. The forms of knowledge showed that it is more varied than a single definition can capture. A fourth question remains - one that education forces us to ask, and that TOK exists to answer: what is knowledge anyway?
The American media theorist Neil Postman spent much of his career documenting what happens when a culture becomes so saturated with information that the question of what it is for disappears entirely. In Technopoly (1992), he described a society in which information had become its own justification - circulated and consumed without any framework for asking whether it was useful, true, or good. He wrote that book the same year I first entered the classroom as a teacher. It was already true then, and that was before the internet, social media and AI. In the 1990s there was genuine optimism in education about the possibilities of a world where every student might have instant access to what Matthew Arnold called "the best that has been thought and said." I was one of those who optimistically wrote about it. But the problem by the year 2000 was never really one of access but rather what we chose to do with access and in the end what we choose to know.
Jerome Bruner spent much of his career working out what that means for how a mind actually learns. For Bruner, knowledge is structured: it is the organising frameworks and narratives that allow the learner to place new experience in relation to what they already know. His concept of the "spiral curriculum" follows from this: you do not teach a subject once and move on, but return to it repeatedly at greater depth, because understanding is not an event but a process of progressive structuring. Schools and teachers provide that structure, and through structure, meaning. This is why background knowledge compounds. Read something built entirely from unfamiliar ideas and you can understand every word and still make no sense of the whole, because nothing in your head is there for the new material to attach to. Read something where most of it is already familiar, and the genuinely new parts slot into place because the structure is already there to hold them. The more you know, the easier it becomes to know more. The less you know, the more easily bored you are by lessons and education in general.
There is a deeper reason why the skills versus knowledge dichotomy dissolves, and it goes back to Ryle and Polanyi. Neither of them was only describing two different kinds of knowledge, knowing-that and knowing-how, sitting side by side. They were describing what happens to knowledge once you have actually learned it: it stops being something you hold in mind and consult, and becomes something you do without noticing you are doing it. That is true of facts as much as it is true of skills.
This matters because working memory is small. Hirsch's chess experts, cited in the provocation, could absorb a new position at a glance only because most of what they were looking at had already been internalised, leaving room to notice the one or two things that were new. The same is true of a skill. A student who has to consciously work out how to evaluate a source, step by step, every single time, has no working memory left over to actually think about what the source says. The method has to disappear into the background the way Polanyi's hammer does, before it can be used for anything.
The real argument, then, is that both facts and methods, what the IB calls content and ATLs, have to go through the same process to become useful: repeated practice until they stop taking up conscious attention. A skill you are still consciously thinking about is not yet a skill you have mastered.
Bringing it together
So what is knowing?
This lesson went from a live argument in education to the foundations of epistemology, and found the two are not as separate as they look. The knowledge-versus-skills debate cannot be resolved without first asking what knowledge is.
Plato's answer - Justified True Belief - was compelling enough to last 2,400 years. Gettier's counter-argument took three pages and changed the conversation permanently. Russell gave us the distinction between knowledge by acquaintance and knowledge by description, which maps onto connaître (knowing a city or person through direct experience) and savoir (knowing that something is the case). Ryle gave us the further distinction between knowing that and knowing how - procedural knowledge, which lives in the body and in trained skill rather than in propositions. Your own languages already encoded much of this. What philosophy did was make it explicit, precise, and available for examination.
The education debate is partly a debate about which of these kinds of knowledge schools value. Big Idea 4 pushed past that: the Swiss Maturité's traditional emphasis on savoir and the IB's emphasis on knowing how to think are two different starting points for the same underlying process. Facts have to become as automatic as skills, and skills have to become as reliable as facts, before either is any use to you under exam pressure or anywhere else. The double diploma puts my students in the unusual position of building both at once, from both directions.
You now have a philosophical vocabulary - JTB, propositional knowledge, procedural knowledge, tacit knowledge, knowledge by acquaintance and description, the Gettier problem - that will carry through the remaining six lessons on Knowledge and the Knower. These are the terms that make the arguments precise.
Next: Lesson 3 - What shapes what we can know?
Questions, assessments, films and other stuff.
Questions to think about
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Is a justified false belief more valuable than an unjustified true one? What does your answer reveal about what you think knowledge is for?
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Gettier’s cases show that something can be JTB without being knowledge. What is missing? Do you think the missing ingredient can be defined?
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Can you know how to do something without knowing that any relevant propositions are true? What does this suggest about the relationship between propositional and procedural knowledge?
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Russell argues that knowledge by acquaintance cannot be fully captured by description. Can you think of an example from your own experience that supports or challenges this?
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Is information the same as knowledge? What would have to be added to information to make it knowledge?
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Is the knowledge-rich curriculum really about knowledge, or about a particular type of knowledge? Which type? And whose?
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French has savoir and connaître; English has only “know.” Does a language that lacks this distinction make certain knowledge problems harder to see? What other distinctions might be hidden inside words you take for granted?
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If knowledge requires justification, can there be unjustified knowledge? Or is that simply a contradiction in terms?
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Postman argues that modern culture produces information without wisdom. Is wisdom a form of knowledge? What would it mean to know wisely?
Exhibition connections
See more exhibition ideas and previous student work here
It is never too early to start to think about your TOK Exhibition, the ideas in this lesson connect strongly to three of the 35 prompts. Start noticing objects in the world around you that speak to these questions.
Prompt #25: "How can we distinguish between knowledge, belief and opinion?"
This lesson is built around exactly this question. A Gettier-type object, something that tracks the structure of justified belief failing to constitute knowledge, could anchor an exhibition exploring where belief ends and knowledge begins. Consider objects that encode a strong conviction that turned out to be wrong, or a belief that was true for the wrong reasons.
Prompt #11: Can new knowledge change established values or beliefs?
Gettier’s 2.5-page paper changed a 2,400-year-old philosophical consensus in one journal article. That is a remarkable example of new knowledge overturning established belief. An exhibition could examine the conditions under which new knowledge has the power to dislodge what was previously taken as certain, in philosophy, in science, in personal life.
Prompt #7: What are the implications of having, or not having, knowledge?
Hirsch argues that skills cannot be taught in the abstract - critical thinking requires a rich store of background knowledge to work on. An exhibition could explore the asymmetry between having and not having knowledge in different contexts, medical diagnosis, political participation, scientific literacy, and what follows from that asymmetry for questions of justice and power.
Feature films
For more see my 10 films for the TOK journey page.
🎬 WATCH — Memento (2000)
Directed by Christopher Nolan
Leonard Shelby cannot form new memories. Since the night he was attacked, everything beyond fifteen minutes dissolves, so he has built an external memory system instead: photographs, handwritten notes, and facts tattooed directly onto his skin.
Each one functions as a justification, evidence he trusts because he wrote it down himself in a moment he can no longer access. The film is Gettier's thought experiment turned into two hours of lived consequence:
Leonard's beliefs are justified by his own system, and some of them are even true, but he has no way to check whether the connection between his evidence and the facts is real or manufactured by someone using his condition against him. By the end you are left asking the same question Smith's coins raise in Big Idea 2: when justification and truth come apart, was any of it ever knowledge at all, or just something Leonard needed to believe in order to keep moving. My students can watch the film here.
Further reading
📚 READ — Is Justified True Belief Knowledge? by Edmund Gettier (1963)
Three pages. Read them. The paper is freely available online and is probably the most consequential short piece in twentieth-century philosophy. You do not need any background to understand it. Gettier writes with exceptional clarity, and reading a primary source that changed its field is a different experience from reading about it. In the library in TOK Books > General TOK books.
📚 READ — The Problems of Philosophy by Bertrand Russell (1912)
Chapter 5 ("Knowledge by Acquaintance and Knowledge by Description") is the key passage for this lesson. The whole book is accessible and rewards reading: Russell wrote it deliberately for non-specialists, and it remains one of the clearest introductions to epistemology ever written. Available free via Project Gutenberg. In the library in TOK Books > General TOK books.
📚 READ — Seven Myths About Education by Daisy Christodoulou (2014)
The introduction and first two chapters are enough for the provocation. Christodoulou writes clearly and polemically; her argument is designed to challenge, and it succeeds. Whether you ultimately agree with her or not, engaging seriously with her case will sharpen your thinking about what schools do and why. In the library in TOK Books > Human science.
📚 READ — Amusing Ourselves to Death by Neil Postman (1985)
Chapter 2 ("Media as Epistemology") is where this lesson's own pull quote comes from, and it makes the book's central argument directly: a culture's dominant medium doesn't just carry information, it decides what counts as serious, coherent, intelligible knowledge in the first place. Postman wrote it about television; read it now and ask what the same argument implies about a feed. In the library in TOK Books > Human science.