Combining Philosophers

All the ideas for Brad W. Hooker, Marcus Rossberg and Xenocrates

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17 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]
15. Nature of Minds / A. Nature of Mind / 2. Psuche
Xenocrates held that the soul had no form or substance, but was number [Xenocrates, by Cicero]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / i. Prescriptivism
Prescriptivism says 'ought' without commitment to act is insincere, or weakly used [Hooker,B]
23. Ethics / B. Contract Ethics / 2. Golden Rule
Universal moral judgements imply the Golden Rule ('do as you would be done by') [Hooker,B]
23. Ethics / E. Utilitarianism / 2. Ideal of Pleasure
Modern utilitarians value knowledge, friendship, autonomy, and achievement, as well as pleasure [Hooker,B]
23. Ethics / E. Utilitarianism / 5. Rule Utilitarianism
Rule-utilitarians prevent things like torture, even on rare occasions when it seems best [Hooker,B]
25. Social Practice / F. Life Issues / 2. Euthanasia
Euthanasia is active or passive, and voluntary, non-voluntary or involuntary [Hooker,B]
Euthanasia may not involve killing, so it is 'killing or not saving, out of concern for that person' [Hooker,B]