Combining Texts

All the ideas for 'The Epistemology of Modality', 'First-order Logic, 2nd-order, Completeness' and 'Against Structural Universals'

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28 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 / B. Properties / 4. Intrinsic Properties
If you think universals are immanent, you must believe them to be sparse, and not every related predicate [Lewis]
8. Modes of Existence / B. Properties / 5. Natural Properties
I assume there could be natural properties that are not instantiated in our world [Lewis]
8. Modes of Existence / B. Properties / 13. Tropes / a. Nature of tropes
Tropes are particular properties, which cannot recur, but can be exact duplicates [Lewis]
8. Modes of Existence / D. Universals / 2. Need for Universals
Universals are meant to give an account of resemblance [Lewis]
8. Modes of Existence / E. Nominalism / 5. Class Nominalism
We can add a primitive natural/unnatural distinction to class nominalism [Lewis]
9. Objects / C. Structure of Objects / 1. Structure of an Object
The 'magical' view of structural universals says they are atoms, even though they have parts [Lewis]
If 'methane' is an atomic structural universal, it has nothing to connect it to its carbon universals [Lewis]
The 'pictorial' view of structural universals says they are wholes made of universals as parts [Lewis]
The structural universal 'methane' needs the universal 'hydrogen' four times over [Lewis]
Butane and Isobutane have the same atoms, but different structures [Lewis]
Structural universals have a necessary connection to the universals forming its parts [Lewis]
We can't get rid of structural universals if there are no simple universals [Lewis]
9. Objects / C. Structure of Objects / 5. Composition of an Object
Composition is not just making new things from old; there are too many counterexamples [Lewis]
9. Objects / C. Structure of Objects / 8. Parts of Objects / c. Wholes from parts
A whole is distinct from its parts, but is not a further addition in ontology [Lewis]
Different things (a toy house and toy car) can be made of the same parts at different times [Lewis]
10. Modality / D. Knowledge of Modality / 4. Conceivable as Possible / a. Conceivable as possible
How do you know you have conceived a thing deeply enough to assess its possibility? [Vaidya]
15. Nature of Minds / C. Capacities of Minds / 3. Abstraction by mind
Maybe abstraction is just mereological subtraction [Lewis]
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
Mathematicians abstract by equivalence classes, but that doesn't turn a many into one [Lewis]