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All the ideas for 'What is Logic?st1=Ian Hacking', 'Epistemology' and 'On Human Nature'

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29 ideas

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
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 / C. Structure of Existence / 3. Levels of Reality
If observation goes up a level, we expect the laws of the lower level to remain in force [Wilson,EO]
8. Modes of Existence / D. Universals / 5. Universals as Concepts
A child first sees objects as distinct, and later as members of groups [Wilson,EO]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
Beliefs are really enabling mechanisms for survival [Wilson,EO]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
The phenomenalist says that to be is to be perceivable [Cardinal/Hayward/Jones]
Linguistic phenomenalism says we can eliminate talk of physical objects [Cardinal/Hayward/Jones]
If we lack enough sense-data, are we to say that parts of reality are 'indeterminate'? [Cardinal/Hayward/Jones]
12. Knowledge Sources / B. Perception / 2. Qualities in Perception / c. Primary qualities
Primary qualities can be described mathematically, unlike secondary qualities [Cardinal/Hayward/Jones]
An object cannot remain an object without its primary qualities [Cardinal/Hayward/Jones]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
My justifications might be very coherent, but totally unconnected to the world [Cardinal/Hayward/Jones]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
Philosophers study the consequences of ethics instead of its origins [Wilson,EO]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
The rules of human decision-making converge and overlap in a 'human nature' [Wilson,EO]
22. Metaethics / B. Value / 2. Values / f. Altruism
We undermine altruism by rewarding it, but we reward it to encourage it [Wilson,EO]
Pure hard-core altruism based on kin selection is the enemy of civilisation [Wilson,EO]
23. Ethics / B. Contract Ethics / 1. Contractarianism
The actor is most convincing who believes that his performance is real [Wilson,EO]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / c. Purpose denied
The only human purpose is that created by our genetic history [Wilson,EO]
27. Natural Reality / G. Biology / 3. Evolution
Cultural evolution is Lamarckian and fast, biological evolution is Darwinian and slow [Wilson,EO]
Over 99 percent of human evolution has been in the hunter-gatherer phase [Wilson,EO]
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
It is estimated that mankind has produced 100,000 religions [Wilson,EO]