AgentSkillsCN

philosophy-of-language

掌握语言哲学——意义、指称、真值、言语行为。用于:语义学、语用学、意义理论、指称。触发词:“意义”、“指称”、“弗雷格”、“涵义”、“克里普克”、“言语行为”、“语义学”、“语用学”、“真值条件”、“命题”、“名称”、“描述”、“刚性指示词”、“自然种类”、“上下文”、“指示词”。

SKILL.md
--- frontmatter
name: philosophy-of-language
description: "Master philosophy of language - meaning, reference, truth, speech acts. Use for: semantics, pragmatics, meaning theory, reference. Triggers: 'meaning', 'reference', 'Frege', 'sense', 'Kripke', 'speech act', 'semantics', 'pragmatics', 'truth conditions', 'propositions', 'names', 'descriptions', 'rigid designator', 'natural kind', 'context', 'indexical'."

Philosophy of Language Skill

Master the philosophical study of language: How do words mean? How does reference work? What is truth?

Core Questions

QuestionIssue
How do words mean?Theory of meaning
How do names refer?Reference theory
What is truth?Truth theories
What do we do with words?Speech act theory

Theories of Meaning

Frege: Sense and Reference

code
FREGEAN SEMANTICS
═════════════════

REFERENCE (Bedeutung)
├── What expression picks out
├── "Venus" refers to Venus
└── Compositional: Reference of whole from parts

SENSE (Sinn)
├── Mode of presentation
├── Cognitive significance
├── "Morning star" vs. "Evening star"
└── Same reference, different sense

WHY BOTH?
├── "Hesperus = Phosphorus" is informative
├── "Hesperus = Hesperus" is trivial
├── Same reference, different sense
└── Sense determines reference

Russell: Descriptions

The Problem: "The present King of France is bald"

  • No King of France exists
  • What does the sentence mean?

Russell's Analysis:

code
"The F is G" =
∃x(Fx ∧ ∀y(Fy → y=x) ∧ Gx)

"There is exactly one F, and it is G"

Not a referring expression but a quantified claim
False (not meaningless) because no unique F exists

Direct Reference

Kripke's Revolution:

  • Names are rigid designators
  • Refer to same thing in all possible worlds
  • Not abbreviated descriptions
code
KRIPKE'S ARGUMENTS
══════════════════

MODAL ARGUMENT:
"Aristotle might not have been a philosopher"
├── Makes sense
├── But "The teacher of Alexander might not have taught Alexander"
│   └── Would make Aristotle not Aristotle
└── Names ≠ descriptions

EPISTEMIC ARGUMENT:
We can discover "Hesperus = Phosphorus"
├── A posteriori necessary truth
├── Same thing in all worlds
└── But discovered, not known a priori

SEMANTIC ARGUMENT:
Reference is causal-historical
├── Not by fitting description
├── Baptism + chain of communication
└── Name-using practice

Meaning and Use

Wittgenstein: Meaning as Use

Early: Meaning is picturing reality Later: "Meaning is use in a language game"

Language Games:

  • Meaning depends on context, rules, practice
  • No single essence to "meaning"
  • Family resemblance

Private Language Argument:

  • No purely private meanings
  • Rule-following requires community
  • Meaning is public

Speech Act Theory (Austin, Searle)

code
SPEECH ACT THEORY
═════════════════

THREE TYPES OF ACTS:

LOCUTIONARY
├── Saying something with meaning
└── Uttering words with sense and reference

ILLOCUTIONARY
├── What you do in saying it
├── Promising, warning, asserting
└── Force of the utterance

PERLOCUTIONARY
├── Effect on hearer
├── Persuading, frightening, amusing
└── Consequences of saying

FELICITY CONDITIONS:
├── Preparatory: Appropriate circumstances
├── Sincerity: Speaker means it
├── Essential: Counts as the act
└── Infelicity: Act fails (not false, but unhappy)

Reference and Names

Descriptivist Theory

Frege/Russell: Names = disguised descriptions

  • "Aristotle" = "The teacher of Alexander" (or cluster)
  • Reference determined by satisfying description

Problems (Kripke):

  • Modal: Could have failed to satisfy description
  • Epistemic: Can discover identity
  • Semantic: Reference even with false beliefs

Causal-Historical Theory

Kripke/Putnam:

  • Initial baptism fixes reference
  • Reference transmitted through causal chain
  • Community-based reference

Natural Kind Terms

Putnam's Twin Earth:

code
TWIN EARTH
══════════

Scenario:
├── Twin Earth exactly like Earth
├── Except "water" is XYZ, not H₂O
├── XYZ phenomenally identical to H₂O
└── 1750: No one knows difference

Question: Does "water" mean the same?

Putnam: No!
├── "Water" on Earth refers to H₂O
├── "Water" on Twin Earth refers to XYZ
├── "Meanings ain't in the head"
└── Natural kind terms refer to natural kinds

Truth

Correspondence Theory

  • Truth = correspondence to facts
  • "Snow is white" is true iff snow is white
  • Problems: What are facts? What is correspondence?

Coherence Theory

  • Truth = coherence with other beliefs
  • System of beliefs that hangs together
  • Problems: Coherent fictions?

Pragmatic Theory

  • Truth = what works
  • Useful beliefs are true
  • Problems: Useful ≠ true

Deflationism

  • "True" is just a device for endorsement
  • "Snow is white" is true = Snow is white
  • No substantial property

Tarski's Semantic Theory

code
TARSKIAN TRUTH
══════════════

T-SCHEMA:
"S" is true iff S

EXAMPLE:
"Snow is white" is true iff snow is white

Requirements:
├── Object language (mentioned)
├── Metalanguage (used)
├── Hierarchy avoids liar paradox
└── Truth defined for formal languages

Context and Indexicals

Indexicals

  • "I", "here", "now", "this"
  • Reference depends on context of utterance
  • Kaplan: Character vs. Content
code
KAPLAN'S THEORY
═══════════════

CHARACTER
├── Rule for determining reference
├── "I" = speaker of context
└── Constant across contexts

CONTENT
├── What's said in context
├── "I am tired" said by me
└── Proposition about me

Contextualism

  • Meaning of many expressions context-dependent
  • Not just indexicals
  • "Knows", "tall", "ready"

Key Vocabulary

TermMeaning
SenseMode of presentation
ReferenceWhat expression picks out
Rigid designatorSame reference in all worlds
IndexicalContext-dependent expression
PropositionWhat is said, content
Speech actAction performed in speaking
Illocutionary forceType of speech act
CompositionalityMeaning of whole from parts
Use theoryMeaning is use
Direct referenceNames refer without sense

Integration with Repository

Related Skills

  • analytic-philosophy: Core tradition
  • logic: Formal semantics

Related Themes

  • thoughts/knowledge/: Language and thought