Week 6: how do we know, and what don't we know
Crasnow and Intemann chapters 4 and 5. Multiple choice and short answer, with the source of every question marked.
Every question here is marked from the reading, which means it was written from the chapters before the lecture happened and can be answered from them. Questions marked from the lecture get added after Wednesday.
- Chapter 4
How do we know?
Printed pages 57 to 79. The nine phases, the rod and frame case, and three answers to what objectivity could mean.
The rod and frame test · what it was built for from the reading
1 Witkin and Asch built the rod and frame apparatus in 1948. What were they originally using it to tell apart?
That is what it was turned into from the 1950s, and it is not what it was built for, which is the thing the case turns on.
Close to what Fausto-Sterling later argued it might be measuring. The question asks what it was built for.
Field-dependent against field-independent. The spatial-ability reading came later, and the apparatus was never designed to test that.
No vision test is involved. Both groups see the rod and the frame perfectly well.
The two words it sorted people into both contain the word for the surroundings you are judging against.
The rod and frame test · what you actually have to do from the reading
2 To complete the test you sit in a dark room in a chair that a male experimenter can tilt, and you have to keep telling him to move the rod a little more, and again, and again, until it is right. What did Anne Fausto-Sterling draw from that in 1985?
She makes no such charge, and the chapter is careful that these were respected studies. Her objection survives everybody acting in good faith.
Women in the 1950s and 1960s were raised not to be demanding and not to make work for a man, and some would plainly have been uncomfortable alone in the dark with a male stranger. So the score may record who was willing to keep asking. Later studies that controlled for this found the gap shrank sharply.
Everybody sits in the same dark. The asymmetry she names is a social one.
A statistical complaint, and hers is about what the apparatus is measuring in the first place.
Ask what the task requires of you socially, and whether a brain difference would explain that part.
The nine phases · why cut it up at all from the reading
3 School teaches that the scientific method is: form a hypothesis, test it, draw a conclusion. The chapter replaces that with nine phases. What is wrong with the school version?
Unpacking test is the whole exercise. Which observations count, how to collect them, what they mean, when you have enough, what else might explain them: a person decides each one, and nothing in nature decides it for them.
The chapter makes no distinction between fields here.
Hypotheses are real and phase 2 is where they come from. The complaint is different.
Nine steps is longer than three, so the move is in the other direction.
Ask which of the three school steps is doing all the hidden work.
The nine phases · the two warnings from the reading
4 The authors attach two warnings to the list of nine phases. Which two?
The chapter exists to deny the first half.
Both matter for an exam. A decision at phase 7 can send you back to revise phase 3, so the list is a tool for looking at inquiry, and no part of it is a timetable. And because phase 1 feeds phase 3 which feeds phase 5, you cannot quarantine values in the early phases.
Neither claim appears, and the examples run across fields.
The first warning says the opposite of this.
One warning is about the order they happen in. The other is about whether they can be kept apart.
The nine phases · which ones this chapter is about from the reading
5 Chapter 3 dealt with phases 1 to 3. This chapter takes phases 4 to 9. Why does the split fall there?
No such division of labour is described.
The reverse of the chapter's argument, which is that values reach into all of them.
Choosing to study breast cancer because it matters to people is uncontroversial. Claiming that a value shaped how the data got read is the claim people resist, so that is where the chapter spends itself.
Funding is not the dividing line used.
Ask which half a sceptic would concede without much argument.
Inductive risk from the reading
6 Deciding you have collected enough evidence is phase 6. The chapter says that decision is never purely factual. Why?
Conventions appear in the chapter's discussion of effect size, and the inductive-risk point is about the cost of error.
A real pressure on research and not the argument here.
The chapter does not treat the decision as arbitrary. It treats it as a judgment with a shape.
That is inductive risk. The cost of a mistake is not something the data can tell you, so somebody weighs it, every time, and what they weigh depends on what they think matters.
- Induction: reasoning up from the cases you have seen to a law covering all of them
Two things feed the decision. One of them is about the world and the other is about what a mistake would do.
Inductive risk · both directions from the reading
7 The authors run the rod and frame case both ways, which is the move that turns it into an argument. What does wrongly accepting that spatial ability is fixed by biology cost?
True of any wrong result and not the cost the chapter traces.
Reputation is not the currency here.
The chapter's whole point is that it does, and it names where.
And the error spreads easily, because the stereotype is already everywhere and people weight evidence that agrees with what they already believe. The other direction has a cost too: wrongly rejecting a real difference loses the chance to understand it and may back policies that cannot work.
- Induction: reasoning up from the cases you have seen to a law covering all of them
Follow it out of the laboratory. Who hears the conclusion, and what do they do differently afterwards?
Phase 8 · the one that does the damage from the reading
8 Social and environmental explanations for the rod and frame results existed, and so did the possibility that the test measures assertiveness. Neither was ruled out. Why does the chapter treat that as the most serious failure?
That is the step from a point about individuals to a point about communities. An explanation that never occurs to you is not an explanation you have ruled out, and the strength of the conclusion depends on a list that somebody's imagination produced.
They were not in the literature waiting to be read, and the case is useful for exactly that reason.
Versions of it are still in use, and papers from 2019 and 2022 still draw the same conclusion.
The chapter says the opposite, and is careful about it. These were respected studies and the alternatives simply did not come to mind.
Inference to the best explanation needs a list to pick from. Ask who writes the list.
Why the authors refuse to call it bad science from the reading
9 In hindsight the rod and frame research looks like sloppy design and hasty conclusions. The authors will not describe it that way. What is their reason?
That is why the chapter cannot end with a demand to try harder. If the entry points are built into how knowing works, the fix has to be structural, which is what the three accounts of objectivity are for.
Later controlled studies found the gap shrank sharply, so some of it has.
A reasonable principle and not the one they use. Theirs is about the present, since the conclusion is still being drawn.
Nothing in the chapter turns on politeness.
- Induction: reasoning up from the cases you have seen to a law covering all of them
If the problem were carelessness, the remedy would be care. Ask why that remedy is not on offer.
Two things called objectivity from the reading
10 The chapter uses two older notions of objectivity constantly. What is the difference between them?
No such division appears.
Degrees come up later, with Longino, and they do not separate these two.
Agent: the person is what makes it trustworthy, because they are detached and have no stake. Both come from the value-free ideal, the view that good science carries no social, political or moral commitment anywhere inside it. Every feminist position in the chapter rejects that ideal, and almost none of them gives up objectivity, which is the combination to be able to state.
Neither term is tied to a kind of work.
One locates the trustworthiness in the procedure and the other in the person running it.
Spontaneous feminist empiricism from the reading
11 One response to sexist results is that the standard methods are fine and were simply applied badly, so following the procedures properly will filter the values out. Why does the chapter reject it?
Nobody broke a rule in that case. The value was in the apparatus, in what it was taken to measure, and in which alternatives came to mind. So the job is no longer removing values but telling legitimate uses from illegitimate ones, and the tidy answer, values are fine in phases 1 and 2 and not after, fails because phase 1 decides what counts as relevant in phase 3.
A practical objection and not the one raised.
Harding names the position, and the chapter engages with its content.
No such general claim is made, and the chapter keeps empirical standards.
- Empiricism: the view that the senses are where knowledge starts
In the rod and frame case, ask which procedural rule was broken.
Longino · what evidence is from the reading
12 Longino's account of objectivity follows from her account of evidence. What is that account?
Measurability is not the condition. The condition is about what connects a fact to a hypothesis.
She calls this contextual empiricism: empiricist because only observable things count, contextual because what they are evidence of depends on the surrounding assumptions. The objectivity argument then follows, since assumptions are shared and invisible to those who share them.
Disputed facts are still evidence on her account, which is why criticism has something to work on.
Consensus appears in her account of communities and it is not her definition of evidence.
Ask what has to be in place before a number counts in favour of anything.
Longino · the housework case from the reading
13 The standard economic account says women earn less, so they have less bargaining power, so they do more housework. It predicts that as a woman's earnings rise her share falls. Julie Brines found in 1994 that when women out-earn their male partners, the men do even less housework than before. What does the case show?
Same number, two contexts, evidence in only one of them. A man who is out-earned has failed at the breadwinner part, so he refuses the part coded female. The feminist commitment that gender is relevant is what made the fact visible, and the displaced assumption had been shared across the field, which is why nobody had been troubled by the anomaly.
Her point is that the second assumption is added to the first, and the bargaining mechanism is not denied.
The finding runs against what that account predicts.
The chapter treats the finding as sound and asks what to make of it.
Ask what the number is evidence of under the first assumption, before you add the second.
Longino · the condition with teeth from the reading
14 Longino names four conditions for transformative criticism: public venues for criticism, uptake, public standards, and tempered equality of intellectual authority. Which one does the real work, and why?
Tempered means the opposite: expertise still counts, and the rule is that nobody with relevant expertise is dismissed for gender, race or class.
Necessary and not sufficient. A community can host criticism and ignore all of it.
Also necessary, and it says nothing about whether anybody listens.
Tolerating criticism costs nothing. The requirement that beliefs move is the one a real community can fail, and it is what makes objectivity come in degrees, since no community meets the four fully.
Three of the four describe arrangements. One describes a change that has to actually happen.
Longino · what diversity is for from the reading
15 On Longino's account diversity acquires a job it did not have before. What is it?
That is an epistemic argument for diversity, on top of the moral one. If no individual can get out from under their own assumptions, the only thing that can is other people, and only people who do not share them.
Productivity is not the claim.
Acceptability is not the argument.
A real pressure and not her reasoning.
Ask what a room full of people who agree about everything cannot do.
Harding · the inversion thesis from the reading
16 Standpoint theory runs on a claim with a name. What does the inversion thesis say?
The value-free ideal, which standpoint theory rejects.
Too strong, and the thesis is about a position being better for noticing certain things.
Two mechanisms, both concrete. A person inside the dominant framework cannot see its assumptions, because they are what seeing is done with. And marginalised knowers can state their own interests, so they can propose different accounts of what the object of study even is.
A pun on the word. The thesis is about who is placed to notice what.
The word inversion points at who is usually assumed to be best placed to know.
Harding · the guard rail from the reading
17 The obvious objection to standpoint theory is that it hands anybody from a marginalised group an automatic advantage in knowing. What does the chapter say to that?
The chapter is explicit that this is not the claim.
Being a woman does not give you the standpoint. Understanding how gender structures the field does. This is the sentence that saves the theory from being silly, and it is the likeliest short-answer prompt in the chapter.
The thesis stands, with this condition attached to it.
No such restriction is made.
Ask what a person would have to have done, beyond being who they are.
Harding · weak and strong objectivity from the reading
18 Harding defines two grades of objectivity. What separates them?
Both grades concern the inquiry as a whole.
Strong: scrutinising all the phases, including whether the subject and the questions suit the goals of the research. Her diagnosis is that good science lacked the methodological resources to detect widely held sexist and androcentric assumptions, so the standards themselves are what need fixing. Androcentric means centred on men, treating male behaviour as the standard case.
The grades are about how much gets examined. Who does it is a separate matter.
No method is privileged either way.
- Empiricism: the view that the senses are where knowledge starts
One grade examines the evidence. The other also examines the question that produced it.
Wylie · the elevator word from the reading
19 Wylie starts from a complaint about the word objective itself, borrowed from Ian Hacking. What is the complaint?
Her problem is that it is too empty.
Calling a result objective says it does not suffer from some failing, without saying what it has. So she gives it content: objectivity belongs to knowledge claims and not to researchers, and a claim is objective to the degree it shows the epistemic virtues, meaning empirical adequacy, inferential robustness, explanatory power, internal coherence, and consistency with other established knowledge.
No etymology is at issue.
Translation is not the problem raised.
The metaphor describes what the word does to the thing it is attached to.
Wylie · where standpoint gets in from the reading
20 Wylie makes objectivity a property of claims, which sounds like it has no room for social position. How does standpoint get into her account anyway?
Her mechanism is about which virtue gets priority. Who scores higher on one is a different claim.
Her account is built so that standpoint improves the judgments the virtues require.
Funding is not her mechanism.
A model that fits the data best is often not the one that explains the most. Somebody chooses, and standpoint improves that choice. This is why her version is the most conservative of the three and the easiest to defend, since it needs no prior commitment about social position.
Ask what happens when two good-making properties of a theory pull against each other.
Chapter 4 · the whole argument in six sentences from the reading
21 A friend who has not done the reading asks why a chapter about the nine phases is in a course on scientific method. Answer in about six sentences.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
Start with the position the chapter is arguing against, and finish with what is left standing.
A strong answer has these moves, in roughly this order.
1. The defence being attacked. Grant that scientists are ordinary people with ordinary opinions. The usual reply is that it does not matter, because method washes the person out.
2. The counter-question. Where is the method, exactly? There is no single procedure, only a long chain of decisions, which the chapter cuts into nine phases.
3. The claim. A human decides every one of them and nothing in nature decides them, so there is no stage at which the person stops mattering.
4. The case. Run the rod and frame test down the chain: somebody decided the apparatus measures spatial ability, somebody read the score as a brain difference, somebody felt that was enough evidence because it was the expected result, and nobody thought of the assertiveness explanation, so nobody ruled it out.
5. The refusal to blame. These were peer-reviewed studies and the entry points look inherent to knowledge production, so the remedy cannot be to try harder.
6. What follows. Objectivity can no longer mean a method anyone could run with the same result, nor a researcher with no commitments. Longino, Harding and Wylie are three attempts to say what it could mean instead, and all three move it off the individual.Compare it with yours.Chapter 4 · the three accounts, side by side from the reading
22 Longino, Harding and Wylie all keep objectivity while rejecting the value-free ideal. State what each attaches the word objective to, and give the one idea that drives each account.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
The three differ in what noun the adjective is attached to. Find that first and the rest follows.
Longino: a community. Driven by her account of evidence. A fact is evidence only through background assumptions, which are shared and invisible to those who share them, so no individual can get out from under their own and only other people can. Objectivity is then a property of how a community is organised, and she names four conditions for transformative criticism, of which uptake has the teeth.
Harding: an inquiry that has been examined from outside. Driven by the inversion thesis, that subordinated people are better placed to notice the assumptions of dominant researchers, with the guard rail that the advantage comes from conscious awareness of power relations, with identity alone giving nothing. Strong objectivity scrutinises all the phases, including whether the question suits the goals.
Wylie: the claim itself. Driven by the complaint that objective is an elevator word. She gives it content as the epistemic virtues, and standpoint enters because the virtues cannot all be maximised at once, so someone must decide which to prioritise.
The line worth adding: Wylie's is the most conservative and the easiest to defend, because it asks you to accept nothing about social position first.Compare it with yours.Chapter 4 · inductive risk, both directions from the reading
23 Explain inductive risk using the rod and frame case, and run the error both ways.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
- Induction: reasoning up from the cases you have seen to a law covering all of them
Name the two things that feed the decision, then price the mistake in each direction.
What it is. Phase 6 is deciding when you have collected enough evidence. How much is enough depends on the probability the hypothesis is true and on what it would cost to be wrong. The second half cannot come from the data, so it is a value judgment, and somebody makes it every time.
Wrongly accepting that spatial ability is biologically fixed by sex reinforces a stereotype, which bears on whether girls are encouraged into mathematics, engineering and architecture. Those are well-paid fields, so the cost shows up in women's earnings. The error also spreads easily, because the stereotype is already widespread and people weight evidence that agrees with what they already think.
Wrongly rejecting it, if it were true, loses the chance to understand a real difference and deal with it fairly, and may support policies that cannot work.
The practical rule the chapter offers: where the cost of error is high and nothing is urgent, collect more and avoid sweeping conclusions. In this case the expected result made less evidence feel like enough.Compare it with yours.- Chapter 5
What don’t we know?
Printed pages 80 to 100. Agnotology, Tuana's five kinds of ignorance, and the five ways ignorance gets made.
Agnotology · what the field studies from the reading
24 Chapter 5 turns the question round. Epistemology asks how knowledge gets made. What does agnotology ask?
Nothing to do with pedagogy.
Error correction is a different topic, and ignorance here is often not an error at all.
It got going in the 1990s with Robert Proctor. Feminists, critical race theorists and decolonial theorists developed a related line called epistemologies of ignorance. Sullivan and Tuana's definition: identifying the forms of ignorance, examining how they are produced and sustained, and asking what role they play in knowledge practices.
Surveys of public knowledge are not the subject.
- Epistemology: a view about what counts as knowledge and how you are allowed to get it
The prefix is the Greek for not knowing. Ask what a field with that name would be a study of.
Ignorance · the thing most people get wrong from the reading
25 Some accounts treat ignorance as simply the absence of knowledge, or the lack of true beliefs. The chapter rejects that. What is its position?
The five kinds include ones nobody chose, and the fifth is not a failing at all.
The chapter spends real time denying this: blinding a clinical trial, restricting how to build a biological weapon, and things said about you that you would rather not know.
Linda Alcoff's phrase is the one to keep. Treating it as a simple absence misses every interesting case, because an absence does not have to be produced and maintained, and these are.
Willful ignorance in particular survives the evidence being put in front of somebody.
An absence needs no explanation. Ask what the chapter thinks needs explaining.
Tuana · the first two kinds from the reading
26 Tuana's first kind is what we do not know but do not care to. Her second is what we do not know that we do not know. Male hormonal contraception and the anatomy of the clitoris illustrate one each. Which goes where, and what separates them?
Tuana's own example of the second kind is the clitoris.
Concealment by an industry is the third kind, and its case is oestrogen risks in contraceptives.
Fame is not the criterion. The criterion is whether anybody ever considered it.
The clitoris is the second, since it was never treated as an object of study at all. Contraception was considered: men would be less willing to accept side effects such as reduced libido, while nobody worried about reduced libido in women, because of the standing assumption that women did not have much desire anyway. The clitoris was different. Study of the genitals was organised around reproduction, the clitoris was taken to play no part in it, so it was not a thing to be ignorant about. It was never rejected as unworthy, because it was never an object of enquiry.
One was put on the table and taken off again. The other never reached the table.
Willful ignorance against self-deception from the reading
27 The chapter draws a careful line between self-deception and willful ignorance. What is it?
The chapter does not sort them that way.
Both involve something the person is doing, and the difference is in what they do with the question.
Both can be about either.
Willful ignorance is fearing it might be true, having an interest in not believing it, so avoiding the question altogether and building ways of minimising whatever evidence turns up. Tuana's phrase is an active ignoring of the oppression of others and one's own role in it. The self-deceiver reaches a conclusion. The willfully ignorant person takes care never to reach one, which is why it is the only kind where the ignorant person is doing work.
One of the two arrives at a belief. The other makes sure never to arrive anywhere.
Mills · white ignorance from the reading
28 Charles Mills gave white ignorance its name in The Racial Contract, 1997. What is his claim?
People with advantages have an interest in believing the world is fair and that what they have is deserved, and no interest at all in learning otherwise, because of what that would imply. So the refusal to understand the conditions others live under is doing a job.
His argument runs the other way: the institutions produce the ignorance.
Spelman's analysis describes how corrections get deflected, and nobody claims it cannot happen.
A gap in a curriculum would be the first kind of ignorance. His claim is stronger and about interest.
Ask what the not-knowing is doing for the person who does not know.
The two quotations put side by side from the reading
29 In 2017 Kate Winslet called the women speaking out about Weinstein incredibly brave and said it was deeply shocking to hear. In the same year, starring in a Woody Allen film, she said she did not know him or anything about that family, that you step away and say you do not know whether any of it is true or false, and that he is an incredible director. What does the chapter draw from the pair?
Actively ignoring the evidence and reaching no conclusion in either direction. That is willful ignorance with a career attached, and the chapter uses two people saying both things in one year so that the pattern cannot be read as one person's inconsistency.
The chapter is analysing a kind of ignorance. It issues no advice.
The two were given in the same year, which is why they are printed together.
The chapter sets out why it is not a word against a word: eyewitness corroboration, experts finding no sign of suggestion, a judge denying custody over the risk, and a prosecutor finding probable cause.
Ask what she would have to do before she could say the allegations were false, and what that would cost.
The fifth kind · loving ignorance from the reading
30 Tuana's fifth kind is what we cannot know: limits on perception, on time and money, and on understanding experiences you have not had. Lugones and Ortega turn it into something other than an excuse. What do they ask for?
The fifth kind is a real limit, and the only one that is no failing.
The opposite of sustained engagement across difference.
Dropping it is what they are arguing against.
Ortega adds that reading about the experiences of women of colour is not enough and produces its own arrogance, so what is wanted is sustained engagement and real relationships. Loving ignorance. The limit is real and it licenses nothing. Lugones calls for a loving perception of those who have been marginalised, and Ortega's sharpening is the part that stings, since it is aimed at people who think they have done the work by reading.
They accept the limit and then say what it does not permit you to do.
The five ways ignorance gets made · discrediting from the reading
31 The chapter names five production strategies: neglect, suppression, discrediting, and two more. Discrediting attacks either the knowledge or the knower. How does attacking the knowledge usually work?
That is attacking the knower, and the question asks about attacking the knowledge.
Disproof would be ordinary science. The strategy works without it, and that is where its cheapness comes from.
They did it by funding conflicting research, exaggerating the uncertainties, and putting non-scientists on television to attack the science. The institutional vehicle is the think tank: it employs researchers, publishes reports, is funded by whoever chose to fund it, has no students and no requirement to be peer reviewed, and its output looks like scholarship, so it is useful to somebody who wants a conclusion to appear independent.
Retraction is not the mechanism described.
You do not have to win the argument. Ask what is enough to stop anybody acting.
The difficulty the chapter raises against itself from the reading
32 Having set out discrediting as a way ignorance gets manufactured, the chapter immediately raises a problem with its own category. What is it?
The chapter gives several cases where it worked.
Their example of a fair challenge is Scott Atlas, a radiologist with no training in epidemiology, advising the White House on masks. Telling fair criticism from manufactured doubt is genuinely hard, and the chapter says so, where it could have pretended the category was clean.
No such claim about its origins is made.
Their examples include Indigenous knowledge and the testimony of individuals.
The problem is that the thing it describes looks exactly like something legitimate.
Chapter 5 · why not knowing needs explaining from the reading
33 Somebody says ignorance is just the absence of knowledge, so a field devoted to it is a waste of time. Answer them, using one case.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
Ask what difference it makes whether a gap was left or made.
The position to argue against: ignorance as a simple lack, an emptiness, a passive state.
The reply: an absence needs no explanation, and these do. Social and cultural forces leave gaps and also make certain things hard or impossible to know. Alcoff's phrase is that ignorance can be a substantive epistemic practice in itself, and treating it as mere neglect misses that.
The case that makes it concrete: there is still no safe effective male hormonal contraceptive. Not because it is hard. In the 1960s it was considered and dropped, on the grounds that men would be less willing to accept side effects such as reduced libido, while nobody worried about reduced libido in women, since the standing assumption was that women did not have much desire anyway. Companies also assumed preventing conception was women's job, so it looked unmarketable. The gap is a decision, and a decision is the kind of thing that has an explanation.
And the point that keeps it balanced: ignorance is not automatically bad. Blinding a clinical trial, restricting how to build a biological weapon, and declining to force patients into a trial are all ignorance on purpose.Compare it with yours.Chapter 5 · Tuana's five kinds from the reading
34 List Tuana's five kinds of ignorance in order, with one case each, and say what the order is tracking.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
Five rows, and the thing that changes down the list is who is doing what.
1. What we do not know but do not care to. Male hormonal contraception: considered and dropped.
2. What we do not know that we do not know. The anatomy of the clitoris: never an object of enquiry at all, because the study of genitals was organised around reproduction.
3. What they do not want us to know. The pharmaceutical industry concealing known risks of oestrogen in contraceptives.
4. Willful ignorance: what we do not know and do not want to. Mills on white ignorance; the Winslet and Lively interviews on Weinstein and Allen.
5. What we cannot know. Real limits of perception, resources, and understanding experience you have not had. Lugones and Ortega's loving ignorance.
What the order tracks: it runs from passive to active and then out the other side. The first two are about what never got asked, differing only in whether anybody considered it. The third is somebody else withholding. The fourth is the only kind where the ignorant person is doing the work. The fifth is no failure at all.
Tuana's own caveat: the list is not exhaustive and one case can sit in several rows at once.Compare it with yours.Chapter 5 · the five production strategies from the reading
35 The taxonomy says what kinds of ignorance there are. The five strategies say how it gets made. Name them and give a case for each.
Write your answer out before you open anything. Reading a model answer you have not attempted teaches almost nothing.
The strategies answer how, where the five kinds answered what.
1. Neglect. Not studying something. Passive when a question never occurs to anyone, active when somebody looks away. Mayor on ancient Mediterranean fossil knowledge, filed as folklore because scholars disregarded non-elite sources, so modern palaeontologists were ignorant of the earliest fossil discoveries. The chapter notes neglect happens across the political spectrum.
2. Suppression. Knowledge exists and fails to travel. Bans, classification, unshared data. It can be chosen by the marginalised themselves: Native American groups withholding fossil knowledge. And through citation: Cuvier wrote up Iroquois and Delaware accounts of mastodon fossils, and the English translation twenty years later left that section out, which made North American fossil discovery look European.
3. Discrediting. Attacking the knowledge, through manufactured uncertainty, which is the tobacco strategy and runs through think tanks. Or attacking the knower, by dismissal for an irrelevant feature. The chapter admits this one mimics reasonable practice.
Note. Add the remaining two from your own copy of the chapter when you read it: this answer is written from the first three, which are the ones the guide sets out in full.Compare it with yours.