Combining Texts

All the ideas for 'A Mathematical Introduction to Logic (2nd)', 'The Theory of Communicative Action' and 'The Nature of Things'

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45 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]
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 / 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 / 7. Natural Sets
A class is natural when everybody can spot further members of it [Quinton]
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]
7. Existence / E. Categories / 5. Category Anti-Realism
Extreme nominalists say all classification is arbitrary convention [Quinton]
8. Modes of Existence / B. Properties / 5. Natural Properties
The naturalness of a class depends as much on the observers as on the objects [Quinton]
Properties imply natural classes which can be picked out by everybody [Quinton]
8. Modes of Existence / D. Universals / 4. Uninstantiated Universals
Uninstantiated properties must be defined using the instantiated ones [Quinton]
9. Objects / A. Existence of Objects / 5. Individuation / b. Individuation by properties
An individual is a union of a group of qualities and a position [Quinton, by Campbell,K]
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]
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]
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]