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All the ideas for 'What is Logic?st1=Ian Hacking', 'The Common-Sense View of Reality' and 'The Moral Problem'

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37 ideas

1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
Metaphysics is hopeless with its present epistemology; common-sense realism is needed [Colvin]
1. Philosophy / F. Analytic Philosophy / 4. Conceptual Analysis
Analysis aims to express the full set of platitudes surrounding a given concept [Smith,M]
2. Reason / D. Definition / 1. Definitions
Defining a set of things by paradigms doesn't pin them down enough [Smith,M]
2. Reason / D. Definition / 3. Types of Definition
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
'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]
7. Existence / D. Theories of Reality / 2. Realism
We can only distinguish self from non-self if there is an inflexible external reality [Colvin]
Common-sense realism rests on our interests and practical life [Colvin]
7. Existence / D. Theories of Reality / 4. Anti-realism
Arguments that objects are unknowable or non-existent assume the knower's existence [Colvin]
If objects are doubted because their appearances change, that presupposes one object [Colvin]
The idea that everything is relations is contradictory; relations are part of the concept of things [Colvin]
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
Capturing all the common sense facts about rationality is almost impossible [Smith,M]
20. Action / C. Motives for Action / 1. Acting on Desires
Goals need desires, and so only desires can motivate us [Smith,M]
A pure desire could be criticised if it were based on a false belief [Smith,M]
A person can have a desire without feeling it [Smith,M]
In the Humean account, desires are not true/false, or subject to any rational criticism [Smith,M]
Subjects may be fallible about the desires which explain their actions [Smith,M]
Humeans (unlike their opponents) say that desires and judgements can separate [Smith,M]
If first- and second-order desires conflict, harmony does not require the second-order to win [Smith,M]
Objective reasons to act might be the systematic desires of a fully rational person [Smith,M]
20. Action / C. Motives for Action / 3. Acting on Reason / a. Practical reason
Motivating reasons are psychological, while normative reasons are external [Smith,M]
Humeans take maximising desire satisfaction as the normative reasons for actions [Smith,M]
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
'Externalists' say moral judgements are not reasons, and maybe not even motives [Smith,M]
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
Moral internalism says a judgement of rightness is thereby motivating [Smith,M]
'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
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
Is valuing something a matter of believing or a matter of desiring? [Smith,M]