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All the ideas for '', 'comedies (frags)' and 'First-order Logic, 2nd-order, Completeness'

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21 ideas

5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
11211 If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
10751 Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg]
10757 Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg]
10759 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
10753 Logical consequence is intuitively semantic, and captured by model theory [Rossberg]
5. Theory of Logic / B. Logical Consequence / 3. Deductive Consequence |-
10752 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
10754 In proof-theory, logical form is shown by the logical constants [Rossberg]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
11212 The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
11210 Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
10756 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
10758 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
10761 Completeness can always be achieved by cunning model-design [Rossberg]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
10755 A deductive system is only incomplete with respect to a formal semantics [Rossberg]
9. Objects / C. Structure of Objects / 6. Constitution of an Object
16066 Additional or removal of any part changes a thing, so people are never the same person [Epicharmus]
13. Knowledge Criteria / E. Relativism / 1. Relativism
436 A dog seems handsome to another a dog, and even a pig to another pig [Epicharmus]
19. Language / F. Communication / 3. Denial
11214 We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
22. Metaethics / C. The Good / 3. Pleasure / f. Dangers of pleasure
442 Pleasures are like pirates - if you are caught they drown you in a sea of pleasures [Epicharmus]
23. Ethics / B. Contract Ethics / 1. Contractarianism
440 Hands wash hands; give that you may get [Epicharmus]
23. Ethics / C. Virtue Theory / 3. Virtues / c. Justice
441 Against a villain, villainy is not a useless weapon [Epicharmus]
28. God / A. Divine Nature / 3. Divine Perfections
439 God knows everything, and nothing is impossible for him [Epicharmus]
29. Religion / D. Religious Issues / 3. Problem of Evil / c. Human Error
443 Human logos is an aspect of divine logos, and is sufficient for successful living [Epicharmus]