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All the ideas for 'fragments/reports', 'Sapiens: brief history of humankind' and 'Principia Mathematica'

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56 ideas

1. Philosophy / B. History of Ideas / 5. Later European Thought
The Scientific Revolution was the discovery of our own ignorance [Harari]
For millenia people didn't know how to convert one type of energy into another [Harari]
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 took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes]
Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend]
'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]
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]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Musical performance can reveal a range of virtues [Damon of Ath.]
23. Ethics / C. Virtue Theory / 4. External Goods / c. Wealth
Money does produce happiness, but only up to a point [Harari]
24. Political Theory / A. Basis of a State / 1. A People / c. A unified people
If a group is bound by gossip, the natural size is 150 people [Harari]
24. Political Theory / A. Basis of a State / 2. Population / a. Human population
Since 1500 human population has increased fourteenfold, and consumption far more [Harari]
People 300m tons; domesticated animals 700m tons; larger wild animals 100m tons [Harari]
24. Political Theory / B. Nature of a State / 1. Purpose of a State
The Nazi aim was to encourage progressive evolution, and avoid degeneration [Harari]
24. Political Theory / B. Nature of a State / 5. Culture
We stabilise societies with dogmas, either of dubious science, or of non-scientific values [Harari]
24. Political Theory / D. Ideologies / 6. Liberalism / b. Liberal individualism
The state fostered individualism, to break the power of family and community [Harari]
24. Political Theory / D. Ideologies / 7. Communitarianism / a. Communitarianism
In 1750 losing your family and community meant death [Harari]
24. Political Theory / D. Ideologies / 11. Capitalism
The sacred command of capitalism is that profits must be used to increase production [Harari]
The main rule of capitalism is that all other goods depend on economic growth [Harari]
The progress of capitalism depends entirely on the new discoveries and gadgets of science [Harari]
In capitalism the rich invest, and the rest of us go shopping [Harari]
25. Social Practice / A. Freedoms / 4. Free market
No market is free of political bias, and markets need protection of their freedoms [Harari]
25. Social Practice / A. Freedoms / 5. Freedom of lifestyle
Freedom may work against us, as individuals can choose to leave, and make fewer commitments [Harari]
25. Social Practice / E. Policies / 1. War / e. Peace
Real peace is the implausibility of war (and not just its absence) [Harari]
25. Social Practice / E. Policies / 4. Taxation
Financing is increasingly through credit rather than taxes; people prefer investing to taxation [Harari]
25. Social Practice / E. Policies / 5. Education / d. Study of history
The more you know about history, the harder it becomes to explain [Harari]
History teaches us that the present was not inevitable, and shows us the possibilities [Harari]
28. God / C. Attitudes to God / 1. Monotheism
In order to explain both order and evil, a single evil creator is best, but no one favours that [Harari]
29. Religion / A. Polytheistic Religion / 1. Animism
Animism is belief that every part of nature is aware and feeling, and can communicate [Harari]
29. Religion / A. Polytheistic Religion / 2. Greek Polytheism
Most polytheist recognise one supreme power or law, behind the various gods [Harari]
Polytheism is open-minded, and rarely persecutes opponents [Harari]
Mythologies are usual contracts with the gods, exchanging devotion for control of nature [Harari]
29. Religion / A. Polytheistic Religion / 4. Dualist Religion
Dualist religions see everything as a battleground of good and evil forces [Harari]
Dualist religions say the cosmos is a battleground, so can’t explain its order [Harari]
Manichaeans and Gnostics: good made spirit, evil made flesh [Harari]
29. Religion / B. Monotheistic Religion / 1. Monotheistic Religion
Monotheism appeared in Egypt in 1350 BCE, when the god Aten was declared supreme [Harari]