Combining Texts

All the ideas for 'The Middle Works (15 vols, ed Boydston)', 'What is Logic?' and 'A World of States of Affairs'

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22 ideas

2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
3. Truth / C. Correspondence Truth / 1. Correspondence Truth
Correspondence may be one-many or many one, as when either p or q make 'p or q' true [Armstrong]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
The various logics are abstractions made from terms like 'if...then' in English [Hacking]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Second-order completeness seems to need intensional entities and possible worlds [Hacking]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking]
5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
7. Existence / D. Theories of Reality / 7. Fictionalism
Without modality, Armstrong falls back on fictionalism to support counterfactual laws [Bird on Armstrong]
8. Modes of Existence / B. Properties / 1. Nature of Properties
Properties are contingently existing beings with multiple locations in space and time [Armstrong, by Lewis]
10. Modality / C. Sources of Modality / 1. Sources of Necessity
The truth-maker for a truth must necessitate that truth [Armstrong]
11. Knowledge Aims / A. Knowledge / 3. Value of Knowledge
The value and truth of knowledge are measured by success in activity [Dewey]
16. Persons / B. Nature of the Self / 1. Self and Consciousness
Habits constitute the self [Dewey]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / e. Character
The good people are those who improve; the bad are those who deteriorate [Dewey]
24. Political Theory / D. Ideologies / 5. Democracy / a. Nature of democracy
Democracy is the development of human nature when it shares in the running of communal activities [Dewey]
Democracy is not just a form of government; it is a mode of shared living [Dewey]
24. Political Theory / D. Ideologies / 6. Liberalism / b. Liberal individualism
Individuality is only developed within groups [Dewey]
26. Natural Theory / C. Causation / 9. General Causation / d. Causal necessity
In recent writings, Armstrong makes a direct identification of necessitation with causation [Armstrong, by Psillos]