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All the ideas for 'fragments/reports', 'works' and 'Contemporary theories of Knowledge (2nd)'

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65 ideas

4. Formal Logic / F. Set Theory ST / 1. Set Theory
Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD]
Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg]
Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / d. Axiom of Unions III
The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / b. Combinatorial sets
Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
There are infinite sets that are not enumerable [Cantor, by Smith,P]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / b. Cantor's paradox
Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / e. Mirimanoff's paradox
The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Cantor took the ordinal numbers to be primary [Cantor, by Tait]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / d. Natural numbers
Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait]
Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine]
Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine]
Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine]
It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner]
The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro]
Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD]
Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten]
Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS]
Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine]
Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Pure mathematics is pure set theory [Cantor]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Cantor says that maths originates only by abstraction from objects [Cantor, by Frege]
11. Knowledge Aims / A. Knowledge / 1. Knowledge
The main epistemological theories are foundationalist, coherence, probabilistic and reliabilist [Pollock/Cruz]
11. Knowledge Aims / B. Certain Knowledge / 1. Certainty
Most people now agree that our reasoning proceeds defeasibly, rather than deductively [Pollock/Cruz]
To believe maximum truths, believe everything; to have infallible beliefs, believe nothing [Pollock/Cruz]
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
Direct realism says justification is partly a function of pure perceptual states, not of beliefs [Pollock/Cruz]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Phenomenalism offered conclusive perceptual knowledge, but conclusive reasons no longer seem essential [Pollock/Cruz]
12. Knowledge Sources / B. Perception / 1. Perception
Perception causes beliefs in us, without inference or justification [Pollock/Cruz]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Sense evidence is not beliefs, because they are about objective properties, not about appearances [Pollock/Cruz]
13. Knowledge Criteria / A. Justification Problems / 1. Justification / a. Justification issues
Bayesian epistemology is Bayes' Theorem plus the 'simple rule' (believe P if it is probable) [Pollock/Cruz]
13. Knowledge Criteria / A. Justification Problems / 3. Internal or External / a. Pro-internalism
Internalism says if anything external varies, the justifiability of the belief does not vary [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / b. Basic beliefs
People rarely have any basic beliefs, and never enough for good foundations [Pollock/Cruz]
Foundationalism requires self-justification, not incorrigibility [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / d. Rational foundations
Reason cannot be an ultimate foundation, because rational justification requires prior beliefs [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / f. Foundationalism critique
Foundationalism is wrong, because either all beliefs are prima facie justified, or none are [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
Negative coherence theories do not require reasons, so have no regress problem [Pollock/Cruz]
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / c. Coherentism critique
Coherence theories fail, because they can't accommodate perception as the basis of knowledge [Pollock/Cruz]
Coherence theories isolate justification from the world [Pollock/Cruz]
13. Knowledge Criteria / C. External Justification / 1. External Justification
Externalism comes as 'probabilism' (probability of truth) and 'reliabilism' (probability of good cognitive process) [Pollock/Cruz]
13. Knowledge Criteria / C. External Justification / 2. Causal Justification
One belief may cause another, without being the basis for the second belief [Pollock/Cruz]
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
We can't start our beliefs from scratch, because we wouldn't know where to start [Pollock/Cruz]
14. Science / C. Induction / 1. Induction
Enumerative induction gives a universal judgement, while statistical induction gives a proportion [Pollock/Cruz]
14. Science / C. Induction / 6. Bayes's Theorem
Since every tautology has a probability of 1, should we believe all tautologies? [Pollock/Cruz]
14. Science / D. Explanation / 3. Best Explanation / a. Best explanation
Scientific confirmation is best viewed as inference to the best explanation [Pollock/Cruz]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend]
18. Thought / E. Abstraction / 2. Abstracta by Selection
Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor]
23. Ethics / A. Egoism / 1. Ethical Egoism
The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius]
27. Natural Reality / C. Space / 3. Points in Space
Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg]
28. God / A. Divine Nature / 2. Divine Nature
Only God is absolutely infinite [Cantor, by Hart,WD]