Combining Philosophers

All the ideas for Aeschylus, Antony Flew and Marcus Rossberg

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14 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]
25. Social Practice / D. Justice / 2. The Law / b. Rule of law
The 'Eumenides' of Aeschylus shows blood feuds replaced by law [Aeschylus, by Grayling]
29. Religion / D. Religious Issues / 1. Religious Commitment / b. Religious Meaning
Claims about God don't seem to claim or deny anything tangible, so evidence is irrelevant [Flew, by PG]
29. Religion / D. Religious Issues / 1. Religious Commitment / d. Religious Falsification
You can't claim a patch of land is tended by a 'gardener' if there is no evidence, and all counter-evidence is rejected [Flew, by PG]
Religious people seem unwilling to accept any evidence that God does not love us, so their claim is unfalsifiable [Flew, by PG]