Combining Texts

All the ideas for 'The Sayings of Confucius', 'On Second-Order Logic' and 'First-order Logic, 2nd-order, Completeness'

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25 ideas

5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
14249 Boolos reinterprets second-order logic as plural logic [Boolos, by Oliver/Smiley]
10830 Second-order logic metatheory is set-theoretic, and second-order validity has set-theoretic problems [Boolos]
10757 Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg]
10751 Second-order logic needs the sets, and its consequence has epistemological problems [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 / C. Ontology of Logic / 1. Ontology of Logic
10829 A sentence can't be a truth of logic if it asserts the existence of certain sets [Boolos]
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 / G. Quantification / 2. Domain of Quantification
10832 '∀x x=x' only means 'everything is identical to itself' if the range of 'everything' is fixed [Boolos]
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]
10834 Weak completeness: if it is valid, it is provable. Strong: it is provable from a set of sentences [Boolos]
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
10755 A deductive system is only incomplete with respect to a formal semantics [Rossberg]
5. Theory of Logic / K. Features of Logics / 6. Compactness
13841 Why should compactness be definitive of logic? [Boolos, by Hacking]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
10833 Many concepts can only be expressed by second-order logic [Boolos]
19. Language / F. Communication / 1. Rhetoric
7357 People who control others with fluent language often end up being hated [Kongzi (Confucius)]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / h. Against ethics
7358 All men prefer outward appearance to true excellence [Kongzi (Confucius)]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
7362 Humans are similar, but social conventions drive us apart (sages and idiots being the exceptions) [Kongzi (Confucius)]
23. Ethics / B. Contract Ethics / 2. Golden Rule
7360 Do not do to others what you would not desire yourself [Kongzi (Confucius)]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / f. The Mean
7359 Excess and deficiency are equally at fault [Kongzi (Confucius)]
23. Ethics / C. Virtue Theory / 3. Virtues / a. Virtues
7363 The virtues of the best people are humility, maganimity, sincerity, diligence, and graciousness [Kongzi (Confucius)]
24. Political Theory / C. Ruling a State / 2. Leaders / d. Elites
7361 Men of the highest calibre avoid political life completely [Kongzi (Confucius)]
24. Political Theory / D. Ideologies / 3. Conservatism
23393 Confucianism assumes that all good developments have happened, and there is only one Way [Norden on Kongzi (Confucius)]