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All the ideas for 'What is Logic?st1=Ian Hacking', 'Boole calculus and the Concept script' and 'The Moral Problem'

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32 ideas

1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
23728 Analysis aims to express the full set of platitudes surrounding a given concept [Smith,M]
2. Reason / D. Definition / 1. Definitions
23744 Defining a set of things by paradigms doesn't pin them down enough [Smith,M]
2. Reason / D. Definition / 3. Types of Definition
13838 A decent modern definition should always imply a semantics [Hacking]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / d. Basic theorems of PL
13834 Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking]
13835 Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking]
13833 '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
13845 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
13840 First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking]
13844 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
13842 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
13837 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
13839 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
13843 If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking]
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
23743 Capturing all the common sense facts about rationality is almost impossible [Smith,M]
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
18265 We don't judge by combining subject and concept; we get a concept by splitting up a judgement [Frege]
20. Action / C. Motives for Action / 1. Acting on Desires
23723 In the Humean account, desires are not true/false, or subject to any rational criticism [Smith,M]
23735 Subjects may be fallible about the desires which explain their actions [Smith,M]
23736 A person can have a desire without feeling it [Smith,M]
23739 Goals need desires, and so only desires can motivate us [Smith,M]
23738 Humeans (unlike their opponents) say that desires and judgements can separate [Smith,M]
23742 If first- and second-order desires conflict, harmony does not require the second-order to win [Smith,M]
23746 Objective reasons to act might be the systematic desires of a fully rational person [Smith,M]
23724 A pure desire could be criticised if it were based on a false belief [Smith,M]
20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason
23733 Motivating reasons are psychological, while normative reasons are external [Smith,M]
23740 Humeans take maximising desire satisfaction as the normative reasons for actions [Smith,M]
23745 We cannot expect even fully rational people to converge on having the same desires for action [Smith,M]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / h. Against ethics
23731 'Externalists' say moral judgements are not reasons, and maybe not even motives [Smith,M]
23732 A person could make a moral judgement without being in any way motivated by it [Smith,M]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / b. Rational ethics
23729 Moral internalism says a judgement of rightness is thereby motivating [Smith,M]
23730 'Rationalism' says the rightness of an action is a reason to perform it [Smith,M]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / h. Expressivism
23727 Expressivists count attitudes as 'moral' if they concern features of things, rather than their mere existence [Smith,M]
22. Metaethics / B. Value / 1. Nature of Value / a. Nature of value
23741 Is valuing something a matter of believing or a matter of desiring? [Smith,M]