Combining Texts

All the ideas for 'The Theory of Communicative Action', 'A Mathematical Introduction to Logic (2nd)' and 'Frege Philosophy of Language (2nd ed)'

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62 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / a. Philosophy as worldly
Habermas seems to make philosophy more democratic [Habermas, by Bowie]
1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
The aim of 'post-metaphysical' philosophy is to interpret the sciences [Habermas, by Finlayson]
1. Philosophy / H. Continental Philosophy / 5. Critical Theory
We can do social philosophy by studying coordinated action through language use [Habermas, by Finlayson]
2. Reason / A. Nature of Reason / 4. Aims of Reason
Rather than instrumental reason, Habermas emphasises its communicative role [Habermas, by Oksala]
2. Reason / A. Nature of Reason / 5. Objectivity
What matters in mathematics is its objectivity, not the existence of the objects [Dummett]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Until the 1960s the only semantics was truth-tables [Enderton]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
'dom R' indicates the 'domain' of objects having a relation [Enderton]
'fld R' indicates the 'field' of all objects in the relation [Enderton]
'ran R' indicates the 'range' of objects being related to [Enderton]
We write F:A→B to indicate that A maps into B (the output of F on A is in B) [Enderton]
'F(x)' is the unique value which F assumes for a value of x [Enderton]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
A relation is 'symmetric' on a set if every ordered pair has the relation in both directions [Enderton]
A relation is 'transitive' if it can be carried over from two ordered pairs to a third [Enderton]
The 'powerset' of a set is all the subsets of a given set [Enderton]
Two sets are 'disjoint' iff their intersection is empty [Enderton]
A 'domain' of a relation is the set of members of ordered pairs in the relation [Enderton]
A 'relation' is a set of ordered pairs [Enderton]
A 'function' is a relation in which each object is related to just one other object [Enderton]
A function 'maps A into B' if the relating things are set A, and the things related to are all in B [Enderton]
A function 'maps A onto B' if the relating things are set A, and the things related to are set B [Enderton]
A relation is 'reflexive' on a set if every member bears the relation to itself [Enderton]
A relation satisfies 'trichotomy' if all pairs are either relations, or contain identical objects [Enderton]
A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second [Enderton]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
The ordered pairs <x,y> can be reduced to the class of sets of the form {{x},{x,y}} [Dummett]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / e. Equivalence classes
An 'equivalence relation' is a reflexive, symmetric and transitive binary relation [Enderton]
We 'partition' a set into distinct subsets, according to each relation on its objects [Enderton]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
To associate a cardinal with each set, we need the Axiom of Choice to find a representative [Dummett]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
Inference not from content, but from the fact that it was said, is 'conversational implicature' [Enderton]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
Validity is either semantic (what preserves truth), or proof-theoretic (following procedures) [Enderton]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A logical truth or tautology is a logical consequence of the empty set [Enderton]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton]
5. Theory of Logic / K. Features of Logics / 3. Soundness
A proof theory is 'sound' if its valid inferences entail semantic validity [Enderton]
5. Theory of Logic / K. Features of Logics / 4. Completeness
A proof theory is 'complete' if semantically valid inferences entail proof-theoretic validity [Enderton]
5. Theory of Logic / K. Features of Logics / 6. Compactness
Proof in finite subsets is sufficient for proof in an infinite set [Enderton]
5. Theory of Logic / K. Features of Logics / 7. Decidability
Expressions are 'decidable' if inclusion in them (or not) can be proved [Enderton]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
For a reasonable language, the set of valid wff's can always be enumerated [Enderton]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / g. Incompleteness of Arithmetic
Intuitionists find the Incompleteness Theorem unsurprising, since proof is intuitive, not formal [Dummett]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Intuitionism says that totality of numbers is only potential, but is still determinate [Dummett]
7. Existence / C. Structure of Existence / 7. Abstract/Concrete / a. Abstract/concrete
Ostension is possible for concreta; abstracta can only be referred to via other objects [Dummett, by Hale]
The concrete/abstract distinction seems crude: in which category is the Mistral? [Dummett]
We don't need a sharp concrete/abstract distinction [Dummett]
We can't say that light is concrete but radio waves abstract [Dummett]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / a. Ontological commitment
The context principle for names rules out a special philosophical sense for 'existence' [Dummett]
The objects we recognise the world as containing depends on the structure of our language [Dummett]
8. Modes of Existence / D. Universals / 1. Universals
We can understand universals by studying predication [Dummett]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
'Nominalism' used to mean denial of universals, but now means denial of abstract objects [Dummett]
9. Objects / A. Existence of Objects / 1. Physical Objects
Concrete objects such as sounds and smells may not be possible objects of ostension [Dummett]
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
Abstract objects may not cause changes, but they can be the subject of change [Dummett]
9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta
If we can intuitively apprehend abstract objects, this makes them observable and causally active [Dummett]
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
Abstract objects must have names that fall within the range of some functional expression [Dummett]
9. Objects / A. Existence of Objects / 2. Abstract Objects / d. Problems with abstracta
If a genuine singular term needs a criterion of identity, we must exclude abstract nouns [Dummett, by Hale]
Abstract objects can never be confronted, and need verbal phrases for reference [Dummett]
9. Objects / A. Existence of Objects / 3. Objects in Thought
There is a modern philosophical notion of 'object', first introduced by Frege [Dummett]
10. Modality / B. Possibility / 8. Conditionals / f. Pragmatics of conditionals
Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton]
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
What is considered a priori changes as language changes [Habermas, by Bowie]
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
Concepts only have a 'functional character', because they map to truth values, not objects [Dummett, by Davidson]
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Since abstract objects cannot be picked out, we must rely on identity statements [Dummett]
19. Language / A. Nature of Meaning / 1. Meaning
To understand a statement is to know what would make it acceptable [Habermas]
19. Language / A. Nature of Meaning / 3. Meaning as Speaker's Intention
Meaning is not fixed by a relation to the external world, but a relation to other speakers [Habermas, by Finlayson]
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
A realistic view of reference is possible for concrete objects, but not for abstract objects [Dummett, by Hale]
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
People endorse equality, universality and inclusiveness, just by their communicative practices [Habermas, by Finlayson]
25. Social Practice / B. Equalities / 2. Political equality
Political involvement is needed, to challenge existing practices [Habermas, by Kymlicka]