Combining Texts

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

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15 ideas

2. Reason / D. Definition / 1. Definitions
The Pythagoreans were the first to offer definitions [Politis, by Politis]
3. Truth / A. Truth Problems / 4. Uses of Truth
'True of' is applicable to things, while 'true' is applicable to words [Politis]
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]
7. Existence / A. Nature of Existence / 3. Being / e. Being and nothing
Maybe 'What is being? is confusing because we can't ask what non-being is like [Politis]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / b. Essence not necessities
Necessary truths can be two-way relational, where essential truths are one-way or intrinsic [Politis]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]