Combining Texts

All the ideas for 'Lysis', 'First-order Logic, 2nd-order, Completeness' and 'works'

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23 ideas

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 / 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]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
23874 Armies and businesses create moralities in which their activity can do no wrong [Marx, by Weil]
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
295 The good is beautiful [Plato]
23. Ethics / C. Virtue Theory / 4. External Goods / d. Friendship
294 People say that friendship exists only between good men [Plato]
24. Political Theory / D. Ideologies / 6. Liberalism / d. Liberal freedom
18662 Liberal freedom is the right to be separate, and ignores the union of man with man [Marx]
24. Political Theory / D. Ideologies / 6. Liberalism / g. Liberalism critique
23372 Liberals want the right to be separate, rather than for people to be united [Marx]
24. Political Theory / D. Ideologies / 7. Communitarianism / a. Communitarianism
20576 Early Marx anticipates communitarian objections to liberalism [Marx, by Oksala]
24. Political Theory / D. Ideologies / 9. Communism
23862 By saying the material dialectic of history aspires to the best, Marx agreed with capitalism [Weil on Marx]
21999 False consciousness results from concealment by the superstructure [Marx, by Singer]
23875 Marx says force is everything, and that the weak will become strong, while remaining the weak [Weil on Marx]
18653 Marx rejected equal rights because they never actually treat people as equals [Marx, by Kymlicka]
24. Political Theory / D. Ideologies / 11. Capitalism
20958 Capitalism changes the world, by socialising the idea of a commodity [Marx, by Bowie]
23876 The essence of capitalism is the subordination of people to things [Marx, by Weil]
20960 Marx thought capitalism was partly liberating, and could make labour and ownership more humane [Marx, by Bowie]