Combining Texts

All the ideas for 'Hippias Major', 'Abortion and the Doctrine of Double Effect' and 'First-order Logic, 2nd-order, Completeness'

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19 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]
Second-order logic needs the sets, and its consequence has epistemological problems [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]
20. Action / C. Motives for Action / 5. Action Dilemmas / b. Double Effect
A 'double effect' is a foreseen but not desired side-effect, which may be forgivable [Foot]
The doctrine of double effect can excuse an outcome because it wasn't directly intended [Foot]
Double effect says foreseeing you will kill someone is not the same as intending it [Foot]
Without double effect, bad men can make us do evil by threatening something worse [Foot]
Double effect seems to rely on a distinction between what we do and what we allow [Foot]
21. Aesthetics / A. Aesthetic Experience / 4. Beauty
What is fine is always difficult [Plato]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
What is fine is the parent of goodness [Plato]
25. Social Practice / F. Life Issues / 3. Abortion
Abortion is puzzling because we do and don't want the unborn child to have rights [Foot]
25. Social Practice / F. Life Issues / 5. Sexual Morality
While sex is very pleasant, it should be in secret, as it looks contemptible [Plato]