Combining Texts

All the ideas for 'fragments/reports', 'Causation' and 'First-order Logic, 2nd-order, Completeness'

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26 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 / 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]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
If dispositions are more fundamental than causes, then they won't conceptually reduce to them [Bird on Lewis]
10. Modality / B. Possibility / 9. Counterfactuals
For true counterfactuals, both antecedent and consequent true is closest to actuality [Lewis]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
Determinism says there can't be two identical worlds up to a time, with identical laws, which then differ [Lewis]
19. Language / D. Propositions / 2. Abstract Propositions / b. Propositions as possible worlds
A proposition is a set of possible worlds where it is true [Lewis]
23. Ethics / A. Egoism / 1. Ethical Egoism
The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius]
26. Natural Theory / C. Causation / 5. Direction of causation
A theory of causation should explain why cause precedes effect, not take it for granted [Lewis, by Field,H]
I reject making the direction of causation axiomatic, since that takes too much for granted [Lewis]
26. Natural Theory / C. Causation / 8. Particular Causation / d. Selecting the cause
It is just individious discrimination to pick out one cause and label it as 'the' cause [Lewis]
The modern regularity view says a cause is a member of a minimal set of sufficient conditions [Lewis]
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
Regularity analyses could make c an effect of e, or an epiphenomenon, or inefficacious, or pre-empted [Lewis]
26. Natural Theory / C. Causation / 9. General Causation / c. Counterfactual causation
The counterfactual view says causes are necessary (rather than sufficient) for their effects [Lewis, by Bird]
Lewis has basic causation, counterfactuals, and a general ancestral (thus handling pre-emption) [Lewis, by Bird]
Counterfactual causation implies all laws are causal, which they aren't [Tooley on Lewis]
My counterfactual analysis applies to particular cases, not generalisations [Lewis]
One event causes another iff there is a causal chain from first to second [Lewis]
26. Natural Theory / D. Laws of Nature / 9. Counterfactual Claims
Lewis's account of counterfactuals is fine if we know what a law of nature is, but it won't explain the latter [Cohen,LJ on Lewis]