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All the ideas for 'reports', 'Particle Physics' and 'Principia Mathematica'

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57 ideas

1. Philosophy / D. Nature of Philosophy / 1. Philosophy
He studied philosophy by suspending his judgement on everything [Pyrrho, by Diog. Laertius]
2. Reason / A. Nature of Reason / 9. Limits of Reason
Sceptics say reason is only an instrument, because reason can only be attacked with reason [Pyrrho, by Diog. Laertius]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
The best known axiomatization of PL is Whitehead/Russell, with four axioms and two rules [Russell/Whitehead, by Hughes/Cresswell]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
Russell saw Reducibility as legitimate for reducing classes to logic [Linsky,B on Russell/Whitehead]
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Russell denies extensional sets, because the null can't be a collection, and the singleton is just its element [Russell/Whitehead, by Shapiro]
We regard classes as mere symbolic or linguistic conveniences [Russell/Whitehead]
5. Theory of Logic / B. Logical Consequence / 7. Strict Implication
Lewis's 'strict implication' preserved Russell's confusion of 'if...then' with implication [Quine on Russell/Whitehead]
Russell's implication means that random sentences imply one another [Lewis,CI on Russell/Whitehead]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Russell unusually saw logic as 'interpreted' (though very general, and neutral) [Russell/Whitehead, by Linsky,B]
5. Theory of Logic / E. Structures of Logic / 6. Relations in Logic
In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / a. Defining numbers
Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend]
Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes]
'Principia' lacks a precise statement of the syntax [Gödel on Russell/Whitehead]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
The ramified theory of types used propositional functions, and covered bound variables [Russell/Whitehead, by George/Velleman]
The Russell/Whitehead type theory was limited, and was not really logic [Friend on Russell/Whitehead]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
In 'Principia Mathematica', logic is exceeded in the axioms of infinity and reducibility, and in the domains [Bernays on Russell/Whitehead]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
Russell and Whitehead consider the paradoxes to indicate that we create mathematical reality [Russell/Whitehead, by Friend]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
To avoid vicious circularity Russell produced ramified type theory, but Ramsey simplified it [Russell/Whitehead, by Shapiro]
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM]
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
If we need a criterion of truth, we need to know whether it is the correct criterion [Pyrrho, by Fogelin]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
The Pyrrhonians attacked the dogmas of professors, not ordinary people [Pyrrho, by Fogelin]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
Academics said that Pyrrhonians were guilty of 'negative dogmatism' [Pyrrho, by Fogelin]
13. Knowledge Criteria / E. Relativism / 1. Relativism
Perception of things depends on their size or quantity (Mode 8) [Pyrrho, by Diog. Laertius]
Individuals vary in responses and feelings (Mode 2) [Pyrrho, by Diog. Laertius]
Perception varies with viewing distance and angle (Mode 7) [Pyrrho, by Diog. Laertius]
Animals vary in their feelings and judgements (Mode 1) [Pyrrho, by Diog. Laertius]
Perception of objects depends on surrounding conditions (Mode 6) [Pyrrho, by Diog. Laertius]
Perception varies with madness or disease (Mode 4) [Pyrrho, by Diog. Laertius]
Perception and judgement depend on comparison (Mode 10) [Pyrrho, by Diog. Laertius]
Judgements vary according to local culture and law (Mode 5) [Pyrrho, by Diog. Laertius]
Perception is affected by expectations (Mode 9) [Pyrrho, by Diog. Laertius]
Objects vary according to which sense perceives them (Mode 3) [Pyrrho, by Diog. Laertius]
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
The multiple relations theory says assertions about propositions are about their ingredients [Russell/Whitehead, by Linsky,B]
A judgement is a complex entity, of mind and various objects [Russell/Whitehead]
The meaning of 'Socrates is human' is completed by a judgement [Russell/Whitehead]
The multiple relation theory of judgement couldn't explain the unity of sentences [Morris,M on Russell/Whitehead]
Only the act of judging completes the meaning of a statement [Russell/Whitehead]
19. Language / D. Propositions / 3. Concrete Propositions
Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead]
26. Natural Theory / C. Causation / 7. Eliminating causation
There are no causes, because they are relative, and alike things can't cause one another [Pyrrho, by Diog. Laertius]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
Motion can't move where it is, and can't move where it isn't, so it can't exist [Pyrrho, by Diog. Laertius]
27. Natural Reality / A. Classical Physics / 1. Mechanics / c. Forces
The strong force has a considerably greater range than the weak force [Martin,BR]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / c. Conservation of energy
If an expected reaction does not occur, that implies a conservation law [Martin,BR]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / a. Electrodynamics
Electron emit and reabsorb photons, which create and reabsorb virtual electrons and positrons [Martin,BR]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / b. Fields
The Higgs field, unlike others, has a nozero value in a state without particles [Martin,BR]
A 'field' is just a region to which points can be assigned in space and time [Martin,BR]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / c. Electrons
Many physicists believe particles have further structure, if only we could see it [Martin,BR]
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / d. Quantum mechanics
Uncertainty allows very brief violations of energy conservation - even shorter with higher energies [Martin,BR]
The Exclusion Principle says no two fermions occupy the same state, with the same numbers [Martin,BR]
27. Natural Reality / B. Modern Physics / 4. Standard Model / b. Standard model
The standard model combines theories of strong interaction, and electromagnetic and weak interaction [Martin,BR]
27. Natural Reality / B. Modern Physics / 4. Standard Model / c. Particle properties
Eletrons don't literally 'spin', because they are point-like [Martin,BR]
The properties of a particle are determined by its quantum numbers and its mass [Martin,BR]
Virtual particles surround any charged particle [Martin,BR]
27. Natural Reality / B. Modern Physics / 5. Unified Models / b. String theory
String theory only has one free parameter (tension) - unlike the standard model with 19 [Martin,BR]
27. Natural Reality / F. Chemistry / 2. Modern Elements
An 'element' is what cannot be decomposed by chemistry [Martin,BR]