Combining Texts

All the ideas for 'Putnam's Paradox', 'The Philosophy of History' and 'Philosophy of Logic'

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22 ideas

3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
For scientific purposes there is a precise concept of 'true-in-L', using set theory [Putnam]
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
Modern notation frees us from Aristotle's restriction of only using two class-names in premises [Putnam]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
The universal syllogism is now expressed as the transitivity of subclasses [Putnam]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC
'⊃' ('if...then') is used with the definition 'Px ⊃ Qx' is short for '¬(Px & ¬Qx)' [Putnam]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
In type theory, 'x ∈ y' is well defined only if x and y are of the appropriate type [Putnam]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Before the late 19th century logic was trivialised by not dealing with relations [Putnam]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Asserting first-order validity implicitly involves second-order reference to classes [Putnam]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Unfashionably, I think logic has an empirical foundation [Putnam]
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
We can identify functions with certain sets - or identify sets with certain functions [Putnam]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Having a valid form doesn't ensure truth, as it may be meaningless [Putnam]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
A consistent theory just needs one model; isomorphic versions will do too, and large domains provide those [Lewis]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
Sets larger than the continuum should be studied in an 'if-then' spirit [Putnam]
7. Existence / D. Theories of Reality / 4. Anti-realism
Anti-realists see the world as imaginary, or lacking joints, or beyond reference, or beyond truth [Lewis]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
Nominalism only makes sense if it is materialist [Putnam]
9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta
Physics is full of non-physical entities, such as space-vectors [Putnam]
9. Objects / C. Structure of Objects / 8. Parts of Objects / b. Sums of parts
A gerrymandered mereological sum can be a mess, but still have natural joints [Lewis]
14. Science / A. Basis of Science / 4. Prediction
Most predictions are uninteresting, and are only sought in order to confirm a theory [Putnam]
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
Causal theories of reference make errors in reference easy [Lewis]
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
Descriptive theories remain part of the theory of reference (with seven mild modifications) [Lewis]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Man is God if he raises himself, by denying his nature and finitude [Hegel]
25. Social Practice / A. Freedoms / 1. Slavery
State slavery is a phase of education, moving towards a full culture [Hegel]
Slavery is unjust, because humanity is essentially free [Hegel]