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All the ideas for 'What is Logic?st1=Ian Hacking', 'fragments/reports' and 'Reality is Not What it Seems'

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35 ideas

1. Philosophy / B. History of Ideas / 2. Ancient Thought
Diogenes of Apollonia was the last natural scientist [Diogenes of Apollonia, by Simplicius]
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]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / a. Achilles paradox
Zeno assumes collecting an infinity of things makes an infinite thing [Rovelli]
7. Existence / B. Change in Existence / 2. Processes
Quantum mechanics deals with processes, rather than with things [Rovelli]
7. Existence / B. Change in Existence / 4. Events / b. Events as primitive
Quantum mechanics describes the world entirely as events [Rovelli]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
Each thing must be in some way unique [Diogenes of Apollonia]
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Start a thesis with something undisputable [Diogenes of Apollonia]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Perception must be an internal matter, because we can fail to perceive when we are preoccupied [Diogenes of Apollonia, by Theophrastus]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
The older Diogenes said the soul is air, made of the smallest particles [Diogenes of Apollonia]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
Diogenes of Apollonia offered the first teleological account of cosmology [Diogenes of Apollonia, by Robinson,TM]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
There are probably no infinities, and 'infinite' names what we do not yet know [Rovelli]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / c. Ultimate substances
Everything is ultimately a variation of one underlying thing [Diogenes of Apollonia]
Air is divine, because it is in and around everything, and arranges everything [Diogenes of Apollonia]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / d. The unlimited
The basic ideas of fields and particles are merged in quantum mechanics [Rovelli]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
Plants and animals can only come into existence if something fixes their species [Diogenes of Apollonia]
Things must retain their essential nature during change, or mixing would be impossible [Diogenes of Apollonia]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
Because it is quantised, a field behaves like a set of packets of energy [Rovelli]
There are about fifteen particles fields, plus a few force fields [Rovelli]
The world consists of quantum fields, with elementary events happening in spacetime [Rovelli]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / c. Electrons
Electrons only exist when they interact, and their being is their combination of quantum leaps [Rovelli]
Electrons are not waves, because their collisions are at a point, and not spread out [Rovelli]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / d. Quantum mechanics
Quantum Theory describes events and possible interactions - not how things are [Rovelli]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
Nature has three aspects: granularity, indeterminacy, and relations [Rovelli]
27. Natural Reality / C. Space / 4. Substantival Space
The world is just particles plus fields; space is the gravitational field [Rovelli]
27. Natural Reality / D. Time / 2. Passage of Time / g. Time's arrow
Only heat distinguishes past from future [Rovelli]