Delegate independent tasks to specialized agents working concurrently with isolated context.
Philosophy of Language Skill
philosophy-of-language
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', 'r...
SKILL.md
Full skill instructions
Philosophy of Language Skill
Master the philosophical study of language: How do words mean? How does reference work? What is truth?
Core Questions
| Question | Issue |
|---|---|
| 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
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:
"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
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)
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:
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
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
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
| Term | Meaning |
|---|---|
| Sense | Mode of presentation |
| Reference | What expression picks out |
| Rigid designator | Same reference in all worlds |
| Indexical | Context-dependent expression |
| Proposition | What is said, content |
| Speech act | Action performed in speaking |
| Illocutionary force | Type of speech act |
| Compositionality | Meaning of whole from parts |
| Use theory | Meaning is use |
| Direct reference | Names refer without sense |
Integration with Repository
Related Skills
analytic-philosophy: Core traditionlogic: Formal semantics
Related Themes
thoughts/knowledge/: Language and thought
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