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All the ideas for 'Precis of 'Limits of Abstraction'', 'Theories of Everything' and 'Higher-Order Logic'

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34 ideas

2. Reason / D. Definition / 2. Aims of Definition
10528 Definitions concern how we should speak, not how things are [Fine,K]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
10301 The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10588 First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
10298 Some say that second-order logic is mathematics, not logic [Shapiro]
10299 If the aim of logic is to codify inferences, second-order logic is useless [Shapiro]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
10300 Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
10290 Second-order variables also range over properties, sets, relations or functions [Shapiro]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10297 The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
10590 Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
10292 Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
10296 The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
10294 Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
10529 If Hume's Principle can define numbers, we needn't worry about its truth [Fine,K]
10530 Hume's Principle is either adequate for number but fails to define properly, or vice versa [Fine,K]
8. Modes of Existence / B. Properties / 11. Properties as Sets
10591 Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
10527 An abstraction principle should not 'inflate', producing more abstractions than objects [Fine,K]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / b. Heat
20624 Work degrades into heat, but not vice versa [Close]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
20623 First Law: energy can change form, but is conserved overall [Close]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / d. Entropy
20625 Third Law: total order and minimum entropy only occurs at absolute zero [Close]
27. Natural Reality / B. Modern Physics / 1. Relativity / a. Special relativity
20622 All motions are relative and ambiguous, but acceleration is the same in all inertial frames [Close]
20628 The electric and magnetic are tightly linked, and viewed according to your own motion [Close]
27. Natural Reality / B. Modern Physics / 1. Relativity / b. General relativity
20635 The general relativity equations relate curvature in space-time to density of energy-momentum [Close]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / a. Electrodynamics
20627 Electric fields have four basic laws (two by Gauss, one by Ampère, one by Faraday) [Close]
20630 Light isn't just emitted in quanta called photons - light is photons [Close]
20637 In general relativity the energy and momentum of photons subjects them to gravity [Close]
20629 Electro-magnetic waves travel at light speed - so light is electromagnetism! [Close]
20632 In QED, electro-magnetism exists in quantum states, emitting and absorbing electrons [Close]
20642 Photon exchange drives the electro-magnetic force [Close]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
20639 Quantum fields contain continual rapid creation and disappearance [Close]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / c. Electrons
20631 Dirac showed how electrons conform to special relativity [Close]
20641 Electrons get their mass by interaction with the Higgs field [Close]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
20626 Modern theories of matter are grounded in heat, work and energy [Close]
27. Natural Reality / B. Modern Physics / 5. Unified Models / a. Electro-weak unity
20633 The Higgs field is an electroweak plasma - but we don't know what stuff it consists of [Close]
27. Natural Reality / C. Space / 6. Space-Time
20640 Space-time is indeterminate foam over short distances [Close]