Combining Texts

All the ideas for 'Introduction to the Theory of Logic', 'Review of 'The Price is Wrong' by B.Christophers' and 'The Correspondence Theory of Truth'

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31 ideas

3. Truth / A. Truth Problems / 5. Truth Bearers
Must sentences make statements to qualify for truth? [O'Connor]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Beliefs must match facts, but also words must match beliefs [O'Connor]
3. Truth / F. Semantic Truth / 2. Semantic Truth
The semantic theory requires sentences as truth-bearers, not propositions [O'Connor]
What does 'true in English' mean? [O'Connor]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / b. Terminology of ST
The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo]
A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
Determinacy: an object is either in a set, or it isn't [Zalabardo]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / l. Axiom of Specification
Specification: Determinate totals of objects always make a set [Zalabardo]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Logic seems to work for unasserted sentences [O'Connor]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
A first-order 'sentence' is a formula with no free variables [Zalabardo]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo]
Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / b. Basic connectives
Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo]
We can do semantics by looking at given propositions, or by building new ones [Zalabardo]
5. Theory of Logic / I. Semantics of Logic / 2. Formal Truth
We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
'Logically true' (|= φ) is true for every truth-assignment [Zalabardo]
Logically true sentences are true in all structures [Zalabardo]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo]
Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
If a set is defined by induction, then proof by induction can be applied to it [Zalabardo]
7. Existence / B. Change in Existence / 4. Events / c. Reduction of events
Events are fast changes which are of interest to us [O'Connor]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
We can't contemplate our beliefs until we have expressed them [O'Connor]
Without language our beliefs are particular and present [O'Connor]
24. Political Theory / D. Ideologies / 11. Capitalism
Markets are transparent, with known prices and activity, and minimal profits [Davies,W]
Capitalists use their exceptional power to impose their own rules, and make the state their ally [Davies,W]
Economies have material, economic and capitalist layers [Davies,W]
Capitalism must mainly rely either on the labour market, or on the financial markets [Davies,W]
Capitalism is the anti-market, with opacity, monopolies, powers, exceptional profits and wealth [Davies,W]