Combining Texts

All the ideas for 'A World of States of Affairs', 'First-order Logic, 2nd-order, Completeness' and 'Against Euthanasia'

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17 ideas

3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Correspondence may be one-many or many one, as when either p or q make 'p or q' true [Armstrong]
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 / 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]
7. Existence / D. Theories of Reality / 7. Fictionalism
Without modality, Armstrong falls back on fictionalism to support counterfactual laws [Bird on Armstrong]
8. Modes of Existence / B. Properties / 1. Nature of Properties
Properties are contingently existing beings with multiple locations in space and time [Armstrong, by Lewis]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
The truth-maker for a truth must necessitate that truth [Armstrong]
25. Social Practice / F. Life Issues / 2. Euthanasia
People will volunteer for euthanasia because they think other people want them dead [Kamisar]
We only allow voluntary euthanasia to someone who is both sane and crazed by pain [Kamisar]
26. Natural Theory / C. Causation / 9. General Causation / d. Causal necessity
In recent writings, Armstrong makes a direct identification of necessitation with causation [Armstrong, by Psillos]