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All the ideas for 'What is Logic?st1=Ian Hacking', 'De primae philosophiae emendatione' and 'Eight Theories of Ethics'

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26 ideas

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
13833 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking]
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]
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]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
12716 The concept of forces or powers best reveals the true concept of substance [Leibniz]
13. Knowledge Criteria / E. Relativism / 3. Subjectivism
6685 'Subjectivism' is an extension of relativism from the social group to the individual [Graham]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / g. Moral responsibility
6699 The chain of consequences may not be the same as the chain of responsibility [Graham]
22. Metaethics / C. The Good / 1. Goodness / g. Consequentialism
6698 Negative consequences are very hard (and possibly impossible) to assess [Graham]
22. Metaethics / C. The Good / 1. Goodness / i. Moral luck
6700 We can't criticise people because of unforeseeable consequences [Graham]
23. Ethics / A. Egoism / 1. Ethical Egoism
6704 Egoism submits to desires, but cannot help form them [Graham]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / h. Right feelings
6701 Rescue operations need spontaneous benevolence, not careful thought [Graham]
23. Ethics / D. Deontological Ethics / 4. Categorical Imperative
6693 'What if everybody did that?' rather misses the point as an objection to cheating [Graham]
23. Ethics / F. Existentialism / 1. Existentialism
6691 It is more plausible to say people can choose between values, than that they can create them [Graham]
23. Ethics / F. Existentialism / 2. Nihilism
6688 Life is only absurd if you expected an explanation and none turns up [Graham]
23. Ethics / F. Existentialism / 5. Existence-Essence
6705 Existentialism may transcend our nature, unlike eudaimonism [Graham]
23. Ethics / F. Existentialism / 6. Authentic Self
6690 A standard problem for existentialism is the 'sincere Nazi' [Graham]
23. Ethics / F. Existentialism / 7. Existential Action
6689 The key to existentialism: the way you make choices is more important than what you choose [Graham]
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
6706 The great religions are much more concerned with the religious life than with ethics [Graham]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
6709 Western religion saves us from death; Eastern religion saves us from immortality [Graham]