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All the ideas for 'Introduction to 'Virtues of Authenticity'', 'The Question of Ontology' and 'First-order Logic, 2nd-order, Completeness'

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22 ideas

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg]
There are at least seven possible systems of semantics for second-order logic [Rossberg]
Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg]
5. Theory of Logic / B. Logical Consequence / 2. Types of Consequence
Logical consequence is intuitively semantic, and captured by model theory [Rossberg]
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg]
5. Theory of Logic / E. Structures of Logic / 1. Logical Form
In proof-theory, logical form is shown by the logical constants [Rossberg]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg]
5. Theory of Logic / J. Model Theory in Logic / 2. Isomorphisms
If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg]
5. Theory of Logic / K. Features of Logics / 4. Completeness
Completeness can always be achieved by cunning model-design [Rossberg]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
A deductive system is only incomplete with respect to a formal semantics [Rossberg]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
The existence of numbers is not a matter of identities, but of constituents of the world [Fine,K]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
It is plausible that x^2 = -1 had no solutions before complex numbers were 'introduced' [Fine,K]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
The indispensability argument shows that nature is non-numerical, not the denial of numbers [Fine,K]
7. Existence / A. Nature of Existence / 1. Nature of Existence
'Exists' is a predicate, not a quantifier; 'electrons exist' is like 'electrons spin' [Fine,K]
7. Existence / A. Nature of Existence / 4. Abstract Existence
Just as we introduced complex numbers, so we introduced sums and temporal parts [Fine,K]
7. Existence / A. Nature of Existence / 6. Criterion for Existence
Real objects are those which figure in the facts that constitute reality [Fine,K]
Being real and being fundamental are separate; Thales's water might be real and divisible [Fine,K]
7. Existence / D. Theories of Reality / 1. Ontologies
For ontology we need, not internal or external views, but a view from outside reality [Fine,K]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / b. Commitment of quantifiers
Ontological claims are often universal, and not a matter of existential quantification [Fine,K]
8. Modes of Existence / D. Universals / 6. Platonic Forms / a. Platonic Forms
Forms are not a theory of universals, but an attempt to explain how predication is possible [Nehamas]
8. Modes of Existence / D. Universals / 6. Platonic Forms / b. Partaking
Only Tallness really is tall, and other inferior tall things merely participate in the tallness [Nehamas]
11. Knowledge Aims / A. Knowledge / 2. Understanding
'Episteme' is better translated as 'understanding' than as 'knowledge' [Nehamas]