Epistemology Skill

Master the theory of knowledge: What is knowledge? How is belief justified? Can we know anything?

Core Questions

The Analysis of Knowledge

Traditional Analysis

JTB: Knowledge = Justified True Belief

S knows that P iff:
1. S believes that P (belief condition)
2. P is true (truth condition)
3. S is justified in believing P (justification condition)

Gettier Problem

Gettier Cases show JTB is not sufficient:

GETTIER CASE #1
═══════════════

Smith has strong evidence that Jones will get the job
(told by company president).

Smith also knows Jones has 10 coins in his pocket.

Smith infers: "The man who will get the job has 10 coins
in his pocket."

Unknown to Smith: HE (Smith) will get the job.
And Smith happens to have 10 coins in his pocket.

Smith's belief is:
✓ Justified (by evidence about Jones)
✓ True (Smith will get job, has 10 coins)
✗ NOT knowledge (too lucky!)

Post-Gettier Theories

Fourth Condition Approaches:

• •No false lemmas
• •Causal connection
• •Defeasibility (no truths that would defeat justification)

Tracking (Nozick):

• •S knows P iff: If P were false, S wouldn't believe P
• •Sensitivity condition

Safety (Sosa, Pritchard):

• •S knows P iff: S couldn't easily have been wrong
• •In nearby possible worlds where S believes P, P is true

Virtue Epistemology:

• •Knowledge = true belief from intellectual virtue
• •Success attributable to cognitive ability

Theories of Justification

Foundationalism

FOUNDATIONALIST STRUCTURE
═════════════════════════

DERIVED BELIEFS
├── Justified by inference
├── From more basic beliefs
└── Not self-justifying

         ↑
         │
    BASIC BELIEFS
    ├── Self-justifying
    ├── Need no support from other beliefs
    └── Foundation of knowledge

Basic Beliefs:

• •Classical: self-evident, incorrigible
• •Modest: defeasibly justified without inference

Coherentism

COHERENTIST STRUCTURE
═════════════════════

    ┌─────────────────────┐
    │                     │
┌───▼───┐           ┌─────┴───┐
│ Belief ├──────────►│ Belief │
│   A    │◄──────────┤   B    │
└───┬────┘           └────┬───┘
    │                     │
    │    ┌─────────┐      │
    └────► Belief  ◄──────┘
         │   C    │
         └────────┘

No foundations; mutual support

Objection: Coherent fiction could be well-justified but false (isolation problem)

Infinitism

• •No basic beliefs
• •No circular justification
• •Infinite regress is not vicious
• •We can always provide further reasons

Internalism vs. Externalism

Skepticism

Cartesian Skepticism

SKEPTICAL ARGUMENT
══════════════════

1. I cannot know I'm not a brain in a vat (BIV)
2. If I know I have hands, I can deduce I'm not a BIV
3. If I can't know the conclusion, I can't know the premise
4. Therefore, I don't know I have hands

CLOSURE PRINCIPLE:
If S knows P, and S knows P→Q, then S can know Q

Responses to Skepticism

Moorean Shift:

• •I know I have hands
• •If I have hands, I'm not a BIV
• •Therefore, I know I'm not a BIV
• •Common sense trumps skeptical premises

Contextualism:

• •"Know" has different standards in different contexts
• •In everyday contexts, we do know
• •In philosophical contexts, standards are higher
• •Both claims are true (in their contexts)

Relevant Alternatives:

• •Knowledge requires ruling out relevant alternatives
• •BIV is not a relevant alternative in normal contexts

Sources of Knowledge

Perception

Direct Realism: We perceive external objects directly Indirect Realism: We perceive sense-data caused by objects Idealism: Objects are mind-dependent

Problems:

• •Perceptual error, illusion
• •Skepticism about external world
• •Theory-ladenness of observation

Reason (A Priori Knowledge)

Rationalism: Some knowledge is innate or a priori Examples: Mathematics, logic, conceptual truths

Problems:

• •How do we access a priori truths?
• •Are they merely analytic?
• •Quine's attack on analytic/synthetic distinction

Testimony

Reductionism: Testimony reducible to other sources Anti-Reductionism: Testimony is fundamental source

Conditions: Speaker sincerity, competence, listener's critical uptake

Memory

Preservative: Memory preserves justification Generative: Memory can generate new knowledge Problems: False memories, reliability

Key Concepts

Epistemic Virtues

Evidence

Evidentialism: Justification proportional to evidence Evidence types: Perceptual, testimonial, inferential

Degrees of Belief (Bayesian)

• •Credences: Degrees of belief (0-1)
• •Conditionalization: Update on evidence
• •Bayes' theorem: P(H|E) = P(E|H)·P(H)/P(E)

Key Vocabulary

Integration with Repository

Related Themes

• •thoughts/knowledge/: Epistemological explorations
• •thoughts/consciousness/: Perception, self-knowledge