Combining Texts

All the ideas for 'First-order Logic, 2nd-order, Completeness', 'Transworld Heir Lines' and 'The Foundations of Empirical Knowledge'

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18 ideas

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg]
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]
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 / C. Ontology of Logic / 1. Ontology of Logic
Logicians like their entities to exhibit a maximum degree of purity [Kaplan]
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]
9. Objects / C. Structure of Objects / 7. Substratum
Models nicely separate particulars from their clothing, and logicians often accept that metaphysically [Kaplan]
10. Modality / E. Possible worlds / 3. Transworld Objects / a. Transworld identity
The simplest solution to transworld identification is to adopt bare particulars [Kaplan]
10. Modality / E. Possible worlds / 3. Transworld Objects / c. Counterparts
Unusual people may have no counterparts, or several [Kaplan]
Essence is a transworld heir line, rather than a collection of properties [Kaplan]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
No one has defended translational phenomenalism since Ayer in 1940 [Ayer, by Kim]
19. Language / A. Nature of Meaning / 8. Synonymy
Sentences might have the same sense when logically equivalent - or never have the same sense [Kaplan]
26. Natural Theory / C. Causation / 9. General Causation / d. Causal necessity
The attribution of necessity to causation is either primitive animism, or confusion with logical necessity [Ayer]