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All the ideas for 'What is Logic?st1=Ian Hacking', 'fragments/reports' and 'Physics and Philosophy'

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38 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]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
If it can't be expressed mathematically, it can't occur in nature? [Heisenberg]
7. Existence / D. Theories of Reality / 2. Realism
Quantum theory shows that exact science does not need dogmatic realism [Heisenberg]
7. Existence / D. Theories of Reality / 4. Anti-realism
Quantum theory does not introduce minds into atomic events [Heisenberg]
8. Modes of Existence / C. Powers and Dispositions / 2. Powers as Basic
A 'probability wave' is a quantitative version of Aristotle's potential, a mid-way type of reality [Heisenberg]
9. Objects / B. Unity of Objects / 2. Substance / a. Substance
We can retain the idea of 'substance', as indestructible mass or energy [Heisenberg]
9. Objects / C. Structure of Objects / 2. Hylomorphism / b. Form as principle
Basic particles have a mathematical form, which is more important than their substance [Heisenberg]
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]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
We give a mathematical account of a system of natural connections in order to clarify them [Heisenberg]
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 / 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 / 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]
26. Natural Theory / D. Laws of Nature / 2. Types of Laws
Seven theories in science: mechanics, heat, electricity, quantum, particles, relativity, life [Heisenberg, by PG]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / a. Energy
Energy is that which moves, and is the substance from which everything is made [Heisenberg]
Energy is an unchanging substance, having many forms, and causing all change [Heisenberg]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
Maxwell introduced real fields, which transferred forces from point to point [Heisenberg]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / d. Quantum mechanics
Radiation interference needs waves, but radiation photoelectric effects needs particles [Heisenberg]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
An atom's stability after collisions needs explaining (which Newton's mechanics can't do) [Heisenberg]
Position is complementary to velocity or momentum, so the whole system is indeterminate [Heisenberg]
It was formerly assumed that electromagnetic waves could not be a reality in themselves [Heisenberg]
27. Natural Reality / C. Space / 4. Substantival Space
So-called 'empty' space is the carrier of geometry and kinematics [Heisenberg]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
In relativity the length of the 'present moment' is relative to distance from the observer [Heisenberg]