The Core Theme - Knowledge and the Knower
Lesson 7 - What does knowing oblige us to do? (Ethics 1)
Knowing something and knowing what to do with it are different problems. This lesson asks whether the gap between them can be crossed.
The lessons so far have mapped how knowledge is formed, how argument and evidence work, and how the systems that produce knowledge shape what counts as knowledge at all. This lesson asks what knowing demands of you. Epistemic responsibility takes three forms that are genuinely distinct. The first concerns assertion: what you are permitted to claim. The second concerns belief: what you are entitled to hold as true. The third concerns action: what you are obliged to do with what you know. Each has a different structure and a different answer.
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This lesson works through a single real case. Watch the provocation below before reading on.
THE PROVOCATION
What You Know Is Not Just Yours
What You Know Is Not Just Yours
ABC v St George's Healthcare
In 2009, a man diagnosed with Huntington's disease refused to allow his doctors to inform his daughter that she might have inherited the condition. She was pregnant at the time. She found out accidentally after giving birth. She later tested positive herself. In 2017 the Court of Appeal ruled that the question of whether the doctors had a legal duty to tell her was arguable - and deserved a full hearing. The lesson examines what knowing demands of you - as a speaker, as a believer, and as someone capable of acting on what you know.
The father believed he was protecting his daughter. He may have been right. Consider: did anyone do something wrong here - and if so, what kind of wrong was it?
Three big ideas about what knowing obliges you to do.
Big Idea 1 - The person who does not care about truth is more dangerous than the person who lies
Frankfurt's distinction sounds obvious once you hear it. Before you heard it, you probably did not have a word for the thing it names.
"It is impossible for someone to lie unless he thinks he knows the truth. Producing bullshit requires no such conviction. A person who lies is thereby responding to the truth, and he is to that extent respectful of it."
Harry Frankfurt, On Bullshit (2005)
Harry Frankfurt's essay On Bullshit begins with a deceptively simple observation: bullshit is everywhere, and we have no serious theory of it. Philosophy has examined lying in careful detail. But the practice of speaking without any regard for truth or falsity has gone largely unexamined.
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The distinction between lying and bullshitting rests on the liar's relationship to truth. To lie, you have to know what the truth is (or believe you do) and then deliberately assert its opposite. The liar recognises the truth and works in full awareness of what he or she is concealing - opposing it while acknowledging its force. The bullshitter stands in a different relationship to truth. Where the liar conceals it, the bullshitter simply does not consider it.
When an advertiser makes claims he has never verified, the question of what is actually true does not arise for him. He is producing whatever will serve his purpose: to gain approval. What comes out is shaped by that purpose, not by any relationship to fact.
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Indifference to truth is more corrosive than opposition to it. A culture of lying is still a culture in which truth matters - the liar must know it in order to depart from it. A culture of bullshit is one in which the distinction between true and false statements has begun to erode as a category of evaluation. Frankfurt argues that bullshit is a greater enemy of the truth than lies precisely because, unlike lying, it tends to attenuate the speaker's own habit of attending to how things actually are. Consider a politician who denies climate change because it conflicts with his economic interests. If he is simply saying whatever fits his agenda without checking whether it is true, that is bullshit: the question of whether the science is accurate is irrelevant to what he produces. Frankfurt's analysis predicts this is more dangerous than deliberate falsehood. The liar at least submits to constraints imposed by the truth he is departing from. The bullshitter submits to no such constraints.
Harry Frankfurt (1929-2023) was an American philosopher best known for his work on moral philosophy, philosophy of mind, and action theory. He taught for many years at Princeton University, where he became professor emeritus. Frankfurt received his BA and PhD from Johns Hopkins University. He is widely known for his concept of "second-order desires" (desires about desires), which helped reshape debates about free will and personal responsibility. Later, he reached a broader audience with On Bullshit (2005), a short philosophical essay that examines truth, sincerity, and communication in modern life.
Frankfurt identifies an obligation that applies to what you say. Clifford identifies one that applies to what you allow yourself to believe. The second turns out to be harder.
Big Idea 2 - It is wrong, always, to believe on insufficient evidence
"It is wrong always, everywhere, and for any one, to believe anything
upon insufficient evidence."
W.K. Clifford, The Ethics of Belief (1877)
William Kingdon Clifford was a Victorian mathematician and philosopher who died at 33, leaving behind a single essay that has been argued about ever since. "The Ethics of Belief"Â (1877) opens with a case that has become one of the most discussed thought experiments in epistemology. A shipowner is about to send an emigrant ship to sea. He has doubts about whether it is seaworthy - it is old, it has needed repairs before, and concerns have been raised. He suppresses those doubts. He tells himself the ship has survived many voyages, that Providence will protect the passengers, that the concerns are probably exaggerated. He works himself into a state of sincere belief that the ship is safe. It sails. It sinks. Everyone on board dies.
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The shipowner believed sincerely that the ship was safe. He was not lying when he told himself it was seaworthy, but for Clifford he was guilty of believing irresponsibly. He had sufficient evidence to doubt the ship's safety. He suppressed that evidence through motivated reasoning, because examining it would have been uncomfortable.
The shipowner's sincere belief was manufactured by a process with no serious engagement with the question of whether the ship was actually safe. And people died as a result.
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Clifford's central claim is that it is wrong, always and everywhere, for anyone to hold a belief on insufficient evidence. He was writing in 1877, before cognitive science existed as a subject. But his argument anticipates what Kahneman demonstrates about motivated reasoning and what Mercier and Sperber show about myside bias. We are built to seek evidence that confirms what we want to believe. The shipowner's cognitive errors are not unusual - they are what humans do. Clifford's point is that this is not an excuse. The obligation to examine your beliefs rigorously is precisely an obligation because it runs against the grain of how the mind naturally operates. We are obliged to engage System 2.
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Return to the Huntington's case. The father has convinced himself that his daughter is better off not knowing. Has he examined that belief with Clifford's rigour? Or has he reasoned toward it because it is the conclusion he needed - because telling her would be painful and would force him to engage with the implications of what his diagnosis means for her life? Clifford does not tell the doctor what to do. But he specifies what questions to ask about the father's belief - and about the doctor's own belief, if the doctor decides the father is probably right.
Big Idea 3 - Knowing about suffering creates an obligation to act
Singer's argument is simple, uncomfortable, and so far unanswered. If you can prevent something bad from happening at no great cost to yourself, you are obliged to prevent it. Distance does not change that.
"If it is in our power to prevent something very bad happening, without thereby sacrificing anything of comparable moral significance, we ought to do it."
Peter Singer, Practical Ethics (2011)
Peter Singer's argument begins with a case that almost everyone finds straightforward. You are walking past a shallow pond. You see a small child who has fallen in and is in danger of drowning. You could easily wade in and save the child. The only cost is ruining your shoes and arriving somewhere late. Almost everyone agrees: you are obliged to save the child. Failing to save the child because you did not want to ruin your shoes would be a serious moral failure.
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Singer's move is to ask what features of this case generate the obligation. The key elements are: a person who will suffer serious harm, the power to prevent that harm, and a cost trivial relative to the harm prevented. None of those elements, Singer argues, depend on physical proximity. If you received a phone call telling you that a child was drowning fifty miles away and that you could save them by driving there, most people would still feel the pull of obligation. The distance is morally irrelevant. What matters is whether the harm is preventable at proportionate cost to you.
Peter Singer - Moral philosophy
Big Think
Peter Singer is an Australian moral philosopher born in 1946, best known for shaping modern applied ethics. A professor at Princeton University, he is a leading advocate of utilitarianism, arguing that we should act to maximise well-being and reduce suffering. His book Animal Liberation helped launch the animal rights movement, while The Life You Can Save promotes effective altruism. Singer's work challenges people to consider global poverty, animal welfare, and moral responsibility in a rigorous, practical way.
Singer argues in "Famine, Affluence, and Morality" (1972) that where we have the power to prevent something bad from happening without sacrificing anything of comparable moral importance, we are morally obliged to do it. This principle has radical implications. Most of us know that preventable suffering exists on a large scale and do relatively little about it. Singer's argument implies that the gap between knowing about preventable suffering and doing nothing about it is a moral failure of the same kind as walking past the drowning child. The knowledge creates the obligation. The distance does not dissolve it. Singer is careful about what the obligation requires. He does not claim you must sacrifice everything. The relevant comparison is between the harm you could prevent and the cost of preventing it. Where the cost to you is trivial relative to the harm prevented, the obligation is strong. Where prevention would require you to sacrifice something of comparable moral importance, the calculus changes. But the threshold for comparable importance is considerably lower than most of us treat it in practice. Discomfort, inconvenience, and the social awkwardness of being seen to care do not approach the moral weight of preventable serious suffering.
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The Huntington's case, for the final time. The daughter will make decisions about her pregnancy and her future that will be shaped by whether she knows she may be at risk. Preventable harm will follow from her not knowing. The doctor knows this. The cost of telling her is real: it will be painful and may violate the father's wishes. Singer's question is whether those costs are comparable in moral weight to the harm that will result from silence. ABC v St George's Healthcare did not resolve that question, but the Court of Appeal accepted in 2017 that it was a real question, not one that patient confidentiality automatically closes off. The doctors' obligation to the daughter was at least arguable. That is Singer's argument, now being asked by English law.
Bringing it together
Where the obligations divide
Frankfurt, Clifford, and Singer are not making the same argument. Each identifies a different point at which knowledge and ethics intersect, and the distinctions between them matter.
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Frankfurt's concern is with assertion - with what you say and the spirit in which you say it. The wrong he identifies is indifference: treating the question of whether your words correspond to reality as irrelevant to what you should say. This wrong can be committed without lying, without producing any immediately identifiable harm, and without any audience noticing. It is a wrong to the infrastructure of honest communication itself.
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Clifford's concern is with belief - with the process by which you arrive at what you hold to be true. The wrong he identifies is irresponsibility: reaching for the belief you need rather than the belief the evidence supports, suppressing doubt through motivated reasoning, manufacturing conviction because examination would be uncomfortable. This wrong can be committed entirely in private, with no external audience at all. It is a wrong to yourself as a knower, and through you to everyone whose lives your beliefs affect.
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Singer's concern is with action - with what knowing requires you to do. The wrong he identifies is passivity: treating knowledge of preventable harm as information rather than obligation, using distance or inconvenience to justify inaction that would be indefensible if the harm were visible and near. This wrong can be committed with perfect honesty and careful epistemic practice. You can believe everything for good reasons and still fail Singer's test by doing nothing with what you know.
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Each argument identifies a different, genuinely independent wrong: you can fail on any one of them while meeting the other two. That independence is what makes them collectively demanding and what makes the Huntington's case a useful test. It implicates all three at once. Lesson 8 will ask whether there is any stable foundation for obligations like these, or whether moral claims of this kind rest on something more secure than preference and intuition.
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Questions, assessments, films and other stuff.
Questions to think about
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Frankfurt argues that bullshit is a greater enemy of truth than lying. What would it mean for a society to take this claim seriously - and what would have to change about how we evaluate political communication?
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Clifford claims it is always wrong to believe on insufficient evidence. Is this too demanding? Are there cases where believing beyond the evidence is not only excusable but required?
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If the shipowner had examined the evidence carefully and still concluded the ship was safe - wrongly, but in good faith - would his moral situation be different? What does Clifford's framework say about well-intentioned epistemic failure?
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Singer's principle implies that most of us, most of the time, are failing a basic moral obligation. Is an ethical framework that condemns ordinary life a useful framework, or does it set a standard so high that it loses practical force?
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Does the doctor in the Huntington's case have an obligation to tell the daughter? Apply Frankfurt, Clifford, and Singer separately. Do they give the same answer?
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Fricker describes testimonial injustice as a wrong done to a person as a knower - not just as a person. Does the daughter in the Huntington's case suffer epistemic injustice as well as harm? What is the difference between the two wrongs?
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Singer argues that distance does not change the moral structure of an obligation. Does this principle apply equally to knowledge - does knowing about a harm at a distance create the same obligation as knowing about it close at hand?
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.
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Prompt 12: Is bias inevitable in the production of knowledge?
Mercier and Sperber's argumentative theory gives this question a precise answer: myside bias is a structural feature of how reason works. An exhibition object connected to a knowledge claim that reflects the interests or prior commitments of its producer - a corporate-funded study or a politically motivated report - allows exploration of whether the bias is accidental or systematic, and whether systematic bias can ever be fully corrected or only acknowledged and managed.
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Prompt 26: Does our knowledge depend on our interactions with other knowers?
This is Mercier and Sperber's central claim in institutional form. Reason achieves reliability through dialogue: the myside bias of each individual is checked by the challenges of others. An exhibition object connected to a collective knowledge-producing institution - a scientific journal, a court of law, a fact-checking organisation, a Wikipedia article - allows exploration of how the social structure of the institution compensates for individual cognitive limits, and what happens when those social structures break down.
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Prompt 28: To what extent is objectivity possible in the production or acquisition of knowledge?
Kahneman's WYSIATI principle - what you see is all there is - means that individual knowers cannot even perceive the alternatives they are not considering. Haidt's rider-elephant model means that even careful moral reasoners are mostly post-hoc rationalising. Objectivity for an individual is severely constrained. An exhibition object that represents a contested knowledge claim - in science, history, or ethics - opens the question of whether objectivity is a property of individual knowers, of methods, or of institutions, and whether any of these can fully achieve it.
Feature films
For more see my 10 films for the TOK journey page.
🎬  WATCH — Spotlight  (2015)
Directed by Tom McCarthy
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The film follows the Boston Globe's Spotlight team as they investigate and expose the systematic concealment of child abuse by Catholic clergy in Boston. For Lesson 7 it works at every level. Frankfurt: the institutional communication from the Church was not lying in Frankfurt's strict sense - many officials appeared not to know the full extent of what they were concealing. It was bullshit: speech designed to produce a certain impression, with indifference to the truth it was obscuring.Â
Clifford: the lawyers, bishops, and officials who convinced themselves the problem was manageable or already addressed were manufacturing belief through motivated reasoning of exactly the kind the shipowner example describes. Singer: the journalists who had the story but delayed publication were - by Singer's framework - failing an obligation created by what they knew. The film is also a precise illustration of Fricker's testimonial injustice: the victims' accounts were not being credited, for reasons connected to the institutional power of those they were accusing. Spotlight won the Academy Award for Best Picture in 2016.  My students can watch the film here.
Further reading
Books
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📚 READ - On Bullshit by Harry G. Frankfurt (2005)
The entire book is 67 pages and reads in under two hours. Frankfurt writes with unusual precision for a philosopher addressing a colloquial subject. The key passages for this lesson are the opening definition of bullshit (pages 1-16), the central distinction between lying and bullshitting (pages 47-56), and the closing argument about sincerity (pages 60-67). Students who read only the middle section risk missing both the setup and the implications. In the library in TOK Books > General TOK books.
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📚 READ - The Ethics of Belief by W.K. Clifford (1877)
The essay is approximately 5,000 words and divided into three sections. The first presents the shipowner case and the central argument: that it is always wrong to believe on insufficient evidence. The second examines when it is legitimate to believe on the authority of others, when tradition and testimony can substitute for direct inquiry, and when they cannot. The third addresses how far belief can legitimately extend beyond direct experience, and what constraints govern inference from the known to the unknown. The first section is essential; the second and third are worth reading but can be treated as extensions. William James's response, "The Will to Believe" (1896), is included in most editions and offers the most significant challenge to Clifford's position. Reading both together produces the debate in full. In the library in TOK Books > Ethics.
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📚 READ - Practical Ethics by Peter Singer (2011, third edition)
Chapter 1 ("About Ethics") establishes Singer's metaethical starting point and is useful preparation for Lesson 8. Chapter 8 ("Rich and Poor") is the fullest statement of the obligation created by knowledge of preventable poverty. Chapter 4 ("What's Wrong with Killing?") is relevant if the Huntington's case is to be followed into questions about what the daughter's knowledge would mean for her pregnancy. Singer's prose is exceptionally clear and the arguments are presented step by step. In the library in TOK Books > Ethics.
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📚 READ - Epistemic Injustice by Miranda Fricker (2007)
Chapter 7 "Hermeneutical Injustice" is directly relevant to the Huntington's case: the daughter cannot fully interpret her own situation because she lacks the information that would give it meaning. This is hermeneutical injustice in Fricker's terms - a specific wrong done to her as a knower. In the library in TOK Books > Ethics.