Chapter 21 Exercises: How Do I Know What's True?

Exercise 1: Thought Experiment — The Gettier Situation

Here is a modified version of a Gettier case, adapted for everyday life:

Your friend has been driving the same Ford pickup truck to work every day for the past three years. You've ridden in this truck multiple times. You've seen the registration. You've heard your friend talk about the truck payments. On the basis of all this evidence, you form the belief: My friend owns a Ford truck.

Now: unknown to you, your friend sold the truck last month. They've been borrowing a neighbor's identical-looking truck while looking for a new vehicle. Your belief that "My friend owns a Ford truck" is false — they don't.

But here's the twist: also unknown to you, your friend signed the papers this morning to purchase a different Ford truck — a used one they found online. The paperwork went through at 9 a.m. It's now 4 p.m. Your friend owns a Ford truck again.

So: your belief My friend owns a Ford truck is now true (they just bought one), it is justified (your years of evidence were reasonable), and you believe it.

But do you know it?

Work through the following questions:

  1. Walk through each condition of the JTB account. Does your belief satisfy each one?
  2. There is clearly something wrong about calling this "knowledge." What is it? What's missing between your justification and the truth of the belief?
  3. This is what philosophers call a "Gettier case" — justified true belief that most people don't want to call knowledge. What does it reveal about what knowledge actually requires, beyond the three JTB conditions?
  4. Some philosophers have responded to Gettier cases by adding a "no false lemmas" condition: you don't know something if your belief is inferred through any false intermediate belief. Does that fix the problem in this case? What false intermediate belief are you relying on?
  5. Others have proposed a "safety" condition: you know something only if you could not easily have been wrong. Does the safety condition work here?
  6. What does this thought experiment suggest about the relationship between certainty and knowledge? Can we ever be genuinely certain of anything?

Exercise 2: Thought Experiment — The Conspiracy Theorist

You're at a dinner party. Someone at the table — let's call him Nathan — is sharing what you immediately recognize as a conspiracy theory. He believes that a recent disease outbreak was deliberately engineered by a powerful pharmaceutical company to create demand for a new vaccine. He's confident, articulate, and has clearly read a lot of material on the topic. He says: "I've looked at this from every angle. The evidence is overwhelming. The mainstream media won't cover it, which just shows how deep this goes."

You don't believe the theory. But Nathan is not obviously stupid or uninformed — he's just operating from a very different set of epistemic standards.

Work through the following questions:

  1. What epistemic standards is Nathan using to form and maintain his belief? Identify at least three specific features of his reasoning that differ from what you would consider good epistemic practice.
  2. What epistemic standards would you apply to evaluate this claim? Be specific: what would count as good evidence for the theory? What would count as good evidence against it? Is the theory falsifiable?
  3. Nathan says that the mainstream media's silence is evidence for the theory. This is a common pattern in conspiracy thinking. What is the epistemological name for this move, and why is it epistemically problematic? (Hint: consider Popper's falsificationism — or think about what kind of evidence would not confirm the theory.)
  4. You want to have a productive conversation with Nathan without simply dismissing him. Using the tools from this chapter — JTB, the concept of justification, epistemic virtues — how would you engage? What question would you ask that might actually open genuine inquiry rather than entrench the disagreement?
  5. Is there an epistemic vice at work in your response to Nathan? Consider: confirmation bias, intellectual arrogance, or dismissiveness. What would genuine epistemic humility look like in this conversation?
  6. Standpoint epistemology asks us to consider: whose knowledge counts, and why. Nathan might argue that he's being dismissed precisely because he's questioning official sources. Is that a legitimate epistemic point, or is it being misused here? How do you tell the difference between genuine epistemic marginalization and the misuse of standpoint language to protect a false belief?

Exercise 3: Reflective Journaling — When I Was Wrong

This exercise is personal and requires honest introspection. There are no wrong answers — only more or less honest ones.

Think of a time when you were confident about something that turned out to be false. It doesn't have to be a grand philosophical error — it could be a political belief you've since revised, an assumption about a person you know, a conviction about what career or relationship path was right for you, a factual claim you confidently made and then had to retract.

Write a reflection (500–800 words) addressing the following:

  1. What did you believe? Describe the belief as specifically as you can.
  2. Why were you confident? What was your justification at the time? Was it based primarily on experience (empiricist), on coherence with your existing worldview (rationalist), on what seemed to work practically (pragmatist), or on what your social community affirmed (standpoint considerations)?
  3. How did you find out you were wrong? Was it a single decisive moment, or a gradual accumulation of evidence? Did someone else tell you, or did you figure it out yourself?
  4. What was your first reaction to the disconfirming evidence? Did you resist it? Try to reinterpret it? Feel relieved? Ashamed?
  5. What does this experience teach you about how you form beliefs? Identify at least one specific epistemic habit — a pattern in how you gather evidence, or how you handle challenges to your views — that this experience revealed.
  6. Which epistemic virtue was most absent in how you held this belief? Intellectual humility? Open-mindedness? Intellectual thoroughness? And which virtue, if you had exercised it, might have led you to correct the belief sooner?

Exercise 4: Which Framework Resonates? Empiricism, Rationalism, or Pragmatism

Read the following three positions and reflect on which feels most like your own natural epistemic instinct:

The Empiricist: "Show me the evidence. I don't trust grand theories built from pure reason — I want observations, data, replicable results. My gold standard is the experiment: a controlled situation where I can see what happens when one variable changes. I'm appropriately skeptical of anything I can't trace to real-world experience."

The Rationalist: "Logic and coherence are my standards. I want to understand how things fit together — whether a claim is consistent with everything else I know, whether the reasoning holds up, whether the argument is valid. A belief that contradicts other things I'm confident of should be questioned, even if the immediate evidence seems to support it."

The Pragmatist: "What matters is whether it works. I'm less interested in abstract questions about what corresponds to an independent reality and more interested in what beliefs actually guide successful action. The test of a belief is how well it allows me to navigate my life — whether it makes accurate predictions, leads to good decisions, generates productive plans."

Respond to the following:

  1. Which stance feels most natural to you? Give a concrete example from your own life where you applied something like this approach.
  2. Can you identify a domain in your life where you operate more like an empiricist, and another where you operate more like a rationalist? What accounts for the difference?
  3. What is the biggest weakness of the framework that resonates most with you? Where does your preferred approach let you down?
  4. Pragmatism is sometimes accused of making truth too subjective — that "what works for me" becomes the measure of truth. Is this accusation fair? How would you respond to it if you find pragmatism compelling?

Exercise 5: Philosophical Dialogue

Imagine a conversation between a Humean empiricist and a Jamesian pragmatist about a single religious belief: the belief that there is a God who listens to prayer.

The Humean empiricist evaluates it this way: prayer is a belief about a matter of fact — the existence of a God and the causal efficacy of communication with that God. To be justified, it requires empirical evidence. What observations support it? Are there controlled studies of prayer's effects? Do prayers have outcomes that can be distinguished from chance? Hume would say: we observe people praying; we observe outcomes; we do not observe the causal connection. By Hume's fork, the belief is either a matter of fact (and needs evidence) or a relation of ideas (and is true by definition, which belief in God's existence is not).

The pragmatist evaluates it differently: does the belief in a listening God work? Does it guide successful action — does it produce comfort, moral motivation, a sense of meaning and connection, practical resilience in difficulty? If so, it has pragmatic cash value. William James argued explicitly that for someone whose religious experience is genuine, and for whom belief in a personal God structures their life in productive and flourishing ways, that belief is — for them — true in the only sense truth has: it works.

Write a 400–600 word dialogue between these two positions. The dialogue should: - Take both positions seriously - Have each position respond to the strongest objection the other raises - End not with a definitive resolution but with a clarified understanding of where the genuine disagreement lies

Then add a paragraph (your own voice) saying where you come down: Is this a case where Hume or James has the better of the argument, or is this one of those genuinely unresolved questions?

Exercise 6: The Dinner Party — Hume, James, and Harding

You are hosting a dinner party for three philosophers: - David Hume — 18th-century Scottish empiricist and skeptic - William James — 19th-century American pragmatist - Sandra Harding — 20th-century feminist epistemologist and philosopher of science

The topic of conversation turns to a burning question of our time: How should individuals evaluate health information they encounter online?

Write a dinner party conversation (600–900 words) in which each philosopher weighs in. The conversation should feel real — not just three position statements, but genuine exchange with agreement, disagreement, and mutual challenge.

Consider: Hume would worry about the reliability of testimony and the limits of what we can actually know from online sources. James would ask what beliefs actually work — what guides people to better health outcomes. Harding would ask whose knowledge counts in health information — who gets believed, whose experience is represented in the evidence, and how social position shapes both who produces and who can access health knowledge.

Exercise 7: Progressive Project Checkpoint — Your Epistemology

This exercise contributes directly to your Personal Philosophy document, which you will complete at the end of Part IV.

Write a 400–600 word "Epistemology" section for your Personal Philosophy, addressing the following:

  1. How do you evaluate claims? When you encounter an unfamiliar claim — a news story, a health recommendation, a factual assertion — what process do you actually use to evaluate it? Be honest about both your ideals and your actual practice.

  2. What are your primary sources of knowledge? Do you tend to rely most heavily on personal experience (empiricism), logical coherence (rationalism), practical results (pragmatism), or the testimony of trusted communities? Do different domains call on different sources?

  3. What are your epistemic blind spots? Name at least two specific ways that your social position, your community, your experiences, or your cognitive habits make it harder for you to see certain things clearly. Think about confirmation bias, standpoint effects, the communities whose knowledge you automatically trust or distrust.

  4. What would it mean to be a more epistemically just person? Drawing on Miranda Fricker's concept of epistemic injustice — whose testimony do you give insufficient weight? Whose knowledge do you fail to take seriously? What would changing that look like in practice?

  5. Which epistemic virtue do you most need to cultivate, and why?

This section will be reviewed and revised at the end of Part IV when you integrate it into your complete Personal Philosophy.