Definition of Knowledge - Philosophy A Level

Overview

• The definition of knowledge is a foundational question in philosophy.
• Plato's definition: Knowledge as justified true belief (JTB).
• Edmund Gettier challenged this definition in 1963 with scenarios (Gettier cases) where justified true belief does not equate to knowledge.
• Alternative definitions aim to define knowledge beyond Gettier issues:
  • Justified true belief (JTB)
  • JTB + No false lemmas
  • Reliabilism
  • Virtue epistemology
  • Infallibilism

Types of Knowledge

• Ability: "Knowledge how" (e.g., knowing how to ride a bike).
• Acquaintance: "Knowledge of" (e.g., knowing Fred well).
• Propositional: "Knowledge that" (e.g., knowing that London is the capital of England).
• Focus on propositional knowledge.

Justified True Belief (JTB)

• Known as the tripartite definition of knowledge.
• Necessary and Sufficient Conditions:
  • Justified, true, and belief are necessary for knowledge.
  • Example: A bachelor is an unmarried man.
  • Gettier cases challenge sufficiency.

Gettier Cases

• Demonstrate justified true belief not sufficient for knowledge due to luck.
• Case 1: Smith's belief about the job and 10 coins.
  • Justified, true belief but not knowledge due to luck.
• Case 2: Disjunction introduction (logical principle):
  • Smith's belief about ownership and location.
  • True due to luck, not knowledge.

Alternative Definitions of Knowledge

JTB + No False Lemmas

• Adds a condition: knowledge must not be inferred from false premises.
• Avoids Gettier issues but faces challenges like the fake barn county example.

Reliabilism

• Knowledge is true belief formed by reliable methods (e.g., good eyesight).
• Advantages: Accounts for knowledge in children and animals.
• Problems: Fake barn county scenario challenges its validity.

Virtue Epistemology

• Links belief with intellectual virtues (e.g., rationality, good memory).
• Linda Zagzebski: Argues Gettier cases challenge all true belief + third condition definitions.
  • Suggests knowledge arises from intellectual virtues.
• Ernest Sosa's Apt Belief:
  • Knowledge as true belief due to intellectual virtues (aptness).
  • Solves Gettier issues by linking truth to intellectual virtues.
  • Problems: Difficulty explaining knowledge in children and animals.

Infallibilism

• Knowledge requires certainty, avoiding doubt.
• Problem: Sets too high a bar for knowledge (e.g., doubt about boiling point).

Conclusion

• Gettier cases significantly challenge the tripartite definition of knowledge.
• Various attempts to refine or redefine knowledge to avoid Gettier problems.
• Philosophical debate on knowledge continues, balancing between certainty and fallibility.