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All the ideas for 'What is Logic?st1=Ian Hacking', 'works' and 'Knowledge and its Limits'

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23 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]
11. Knowledge Aims / A. Knowledge / 4. Belief / c. Aim of beliefs
4760 Belief aims at knowledge (rather than truth), and mere believing is a kind of botched knowing [Williamson]
11. Knowledge Aims / A. Knowledge / 7. Knowledge First
19512 Don't analyse knowledge; use knowledge to analyse other concepts in epistemology [Williamson, by DeRose]
14. Science / B. Scientific Theories / 3. Instrumentalism
7621 Special relativity, unlike general relativity, was operationalist in spirit [Putnam on Einstein]
26. Natural Theory / C. Causation / 1. Causation
22955 Einstein took causation to be the bedrock of physics [Einstein, by Coveney/Highfield]
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
20638 General relativity assumes laws of nature are the same in all frames of reference [Einstein, by Close]
27. Natural Reality / A. Classical Physics / 1. Mechanics / d. Gravity
20636 Newton is a special case of Einstein's general theory, with an infinite speed of light [Einstein, by Close]
27. Natural Reality / B. Modern Physics / 1. Relativity / a. Special relativity
21230 The theory is 'special' because it sticks to observers moving straight, at constant speeds [Einstein, by Farmelo]
21231 Assume the speed of light is constant for all observers, and the laws of physics are the same [Einstein, by Farmelo]
27. Natural Reality / B. Modern Physics / 1. Relativity / b. General relativity
20634 General Relativity says there is no absolute force or acceleration [Einstein, by Close]
27. Natural Reality / B. Modern Physics / 4. Standard Model / d. Mass
20648 Mass is a measure of energy content [Einstein]
27. Natural Reality / C. Space / 6. Space-Time
21232 Space-time arises from the connection between measurements of space and of time [Einstein, by Farmelo]
28. God / C. Attitudes to God / 5. Atheism
7626 I do not believe in a personal God [Einstein]