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All the ideas for 'What is Logic?st1=Ian Hacking', 'Identity and Essence' and 'works'

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39 ideas

1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / a. Philosophy as worldly
Ideals and metaphysics are practical, not imaginative or speculative [Green,TH, by Muirhead]
2. Reason / D. Definition / 3. Types of Definition
A decent modern definition should always imply a semantics [Hacking]
3. Truth / D. Coherence Truth / 1. Coherence Truth
Truth is a relation to a whole of organised knowledge in the collection of rational minds [Green,TH, by Muirhead]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
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]
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]
9. Objects / A. Existence of Objects / 5. Individuation / a. Individuation
Indiscernibility is a necessary and sufficient condition for identity [Brody]
9. Objects / A. Existence of Objects / 5. Individuation / e. Individuation by kind
Brody bases sortal essentialism on properties required throughout something's existence [Brody, by Mackie,P]
9. Objects / C. Structure of Objects / 2. Hylomorphism / a. Hylomorphism
Modern emphasis is on properties had essentially; traditional emphasis is on sort-defining properties [Brody]
9. Objects / D. Essence of Objects / 5. Essence as Kind
A sortal essence is a property which once possessed always possessed [Brody, by Mackie,P]
Maybe essential properties are those which determine a natural kind? [Brody]
9. Objects / D. Essence of Objects / 6. Essence as Unifier
De re essentialism standardly says all possible objects identical with a have a's essential properties [Brody]
9. Objects / D. Essence of Objects / 7. Essence and Necessity / a. Essence as necessary properties
Essentially, a has P, always had P, must have had P, and has never had a future without P [Brody]
An object having a property essentially is equivalent to its having it necessarily [Brody]
9. Objects / D. Essence of Objects / 8. Essence as Explanatory
Essentialism is justified if the essential properties of things explain their other properties [Brody]
9. Objects / D. Essence of Objects / 12. Essential Parts
Mereological essentialism says that every part that ensures the existence is essential [Brody]
9. Objects / E. Objects over Time / 12. Origin as Essential
Interrupted objects have two first moments of existence, which could be two beginnings [Brody]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
a and b share all properties; so they share being-identical-with-a; so a = b [Brody]
10. Modality / E. Possible worlds / 3. Transworld Objects / b. Rigid designation
Identity across possible worlds is prior to rigid designation [Brody]
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / d. Absolute idealism
All knowledge rests on a fundamental unity between the knower and what is known [Green,TH, by Muirhead]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
The ultimate test for truth is the systematic interdependence in nature [Green,TH, by Muirhead]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
What is distinctive of human life is the desire for self-improvement [Green,TH, by Muirhead]
23. Ethics / A. Egoism / 2. Hedonism
Hedonism offers no satisfaction, because what we desire is self-betterment [Green,TH, by Muirhead]
24. Political Theory / B. Nature of a State / 2. State Legitimacy / d. General will
Politics is compromises, which seem supported by a social contract, but express the will of no one [Green,TH]
24. Political Theory / B. Nature of a State / 4. Citizenship
The ideal is a society in which all citizens are ladies and gentlemen [Green,TH]
Enfranchisement is an end in itself; it makes a person moral, and gives a basis for respect [Green,TH]
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
The good is identified by the capacities of its participants [Green,TH, by Muirhead]
24. Political Theory / D. Ideologies / 6. Liberalism / b. Liberal individualism
A true state is only unified and stabilised by acknowledging individuality [Green,TH, by Muirhead]
24. Political Theory / D. Ideologies / 7. Communitarianism / a. Communitarianism
People only develop their personality through co-operation with the social whole [Green,TH, by Muirhead]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
If something develops, its true nature is embodied in its end [Green,TH]
28. God / A. Divine Nature / 1. God
God is the ideal end of the mature mind's final development [Green,TH]
28. God / C. Attitudes to God / 4. God Reflects Humanity
God is the realisation of the possibilities of each man's self [Green,TH]