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All the ideas for 'What is Logic?st1=Ian Hacking', 'Philosophy of Chemistry' and 'The Case against Closure (and reply)'

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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
'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]
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / c. Knowledge closure
Closure says if you know P, and also know P implies Q, then you must know Q [Dretske]
We needn't regret the implications of our regrets; regretting drinking too much implies the past is real [Dretske]
Reasons for believing P may not transmit to its implication, Q [Dretske]
Knowing by visual perception is not the same as knowing by implication [Dretske]
The only way to preserve our homely truths is to abandon closure [Dretske]
P may imply Q, but evidence for P doesn't imply evidence for Q, so closure fails [Dretske]
We know past events by memory, but we don't know the past is real (an implication) by memory [Dretske]
14. Science / D. Explanation / 2. Types of Explanation / i. Explanations by mechanism
Thick mechanisms map whole reactions, and thin mechanism chart the steps [Weisberg/Needham/Hendry]
Using mechanisms as explanatory schemes began in chemistry [Weisberg/Needham/Hendry]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
Lavoisier's elements included four types of earth [Weisberg/Needham/Hendry]
27. Natural Reality / F. Chemistry / 1. Chemistry
Over 100,000,000 compounds have been discovered or synthesised [Weisberg/Needham/Hendry]
Water molecules dissociate, and form large polymers, explaining its properties [Weisberg/Needham/Hendry]
It is unlikely that chemistry will ever be reduced to physics [Weisberg/Needham/Hendry]
Quantum theory won't tell us which structure a set of atoms will form [Weisberg/Needham/Hendry]
For temperature to be mean kinetic energy, a state of equilibrium is also required [Weisberg/Needham/Hendry]
'H2O' just gives the element proportions, not the microstructure [Weisberg/Needham/Hendry]
27. Natural Reality / F. Chemistry / 2. Modern Elements
Isotopes (such as those of hydrogen) can vary in their rates of chemical reaction [Weisberg/Needham/Hendry]
27. Natural Reality / F. Chemistry / 3. Periodic Table
Mendeleev systematised the elements, and also gave an account of their nature [Weisberg/Needham/Hendry]